Low moisture permeability laminate construction

ABSTRACT

An article having a fluid permeation prevention layer, such as a pneumatic tire or hose. A tire for example includes an outer tread layer, intermediate sidewall and carcass layers and an innermost air permeation prevention layer: (i) the air permeation prevention (APP) layer having an upper and a lower surface, the layer having a polymer composition exhibiting an air permeation coefficient (APC) of about 25×1O′12 cc cm/cm2 sec cmHg (at 30* C) or less and a Young&#39;s modulus of about 1 MPa to about 500 MPa, the polymer composition comprising: (A) at least 10 wt % of at least one. thermoplastic resin component having an APC of about 25×1O″12 cc cm/cm2 sec cmHg (at 30° C.) or less and a Young&#39;s modulus of more than 500 MPa, which is preferably a polyamide resin or mixture, and (B) at least 10 wt % of at least one elastomer component having an APC of more than about 25×10″12 cc cm/cm2 sec cmHg (at 30° C.) and a Young&#39;s modulus of not more than 500 MPa, which elastomer component is preferably a halogen-containing rubber or mixture, the total amount (A)+(B) being not less than about 30 wt %, and the elastomer component is a dispersed vulcanized, discontinuous phase in the thermoplastic resin matrix; and (ii) at least one thermoplastic laminate layer bonded to at least said lower surface of the APP layer, the thermoplastic layer comprising a film-forming, semi-crystalline, substantially hydrophobic carbon chain polymer having a glass transition temperature, Tg, of less than about −200 C.

FIELD OF THE INVENTION

The present invention relates to thermoplastic elastomer compositionsparticularly useful for tire and other industrial rubber applicationsand to processes for producing such compositions. Disclosed herein arecompositions useful in multilayer or laminate constructions, for examplein tire construction, especially an air and moisture impermeable layerwithin a tire carcass, often referred to as a tire innerliner.Alternatively, such a construction is useful in hose constructions,particularly the inner layer of such constructions. At least one of thelayers comprises nylon and halogenated isobutylene-containing elastomer.In one aspect, the present invention relates to an improvedthermoplastic elastomer composition having excellent heat resistance,durability and flexibility, while possessing superior air and moistureimpermeability for applications in a tire innerliner and in a barrierlayer. In particular, the present invention relates to a softthermoplastic elastomer composition laminated to one or more thinhydrophobic flexible thermoplastic layers.

BACKGROUND OF THE INVENTION

EP722850B1 discloses a low-permeability thermoplastic elastomercomposition that is superior as a gas-barrier layer in pneumatic tires.This thermoplastic elastomer composition comprises a low-permeabilitythermoplastic matrix, such as polyamide or a blend of polyamides, inwhich there is dispersed a low-permeability rubber, such as brominatedpoly(isobutylene-co-paramethylstyrene), referred to hereinafter as BIMS.In EP857761A1 and EP969039A1, the viscosity ratio of the thermoplasticmatrix and the dispersed rubber phase was specified both as a functionof the volume fraction ratio and, independently, to be close to a valueof one in order to produce a high concentration of small particle sizevulcanized rubber particles dispersed in a thermoplastic phase.EP969039A1 further discloses that small particle size rubber dispersedin a thermoplastic resin matrix was important in order to achieveacceptable durability of the resulting composition, particularly wheresuch compositions are intended to be used as innerliners in pneumatictires.

Compositions exhibiting low gas permeability performance (i.e.,functioning as a gas barrier) composed of thermoplasticresin/thermoplastic resin-based blends such as a high densitypolyethylene resin and nylon 6 or nylon 66 (HDPE/PA6.66), a polyethyleneterephthalate and aromatic nylon (PET/MXD6), a polyethyleneterephthalate and vinyl alcohol-ethylene copolymer (PET/EVOH), where onethermoplastic resin is layered over the other layer to form plurallayers by molding, and processes for producing the same, are disclosed,for example, by I. Hata, Kobunshi (Polymers), 40 (4), 244 (1991).Further, an application regarding the use of such a composition as theinnerliner layer of a tire is disclosed in Japanese Patent ApplicationNo. 7-55929. However, since these materials are thermoplasticresin/thermoplastic resin blends, while they are superior in gas barrierperformance, they lack flexibility, and therefore, such films are liableto break when the tire is in use.

Thus, nylon polymers can be useful in polymer compositions for reducingthe permeability of air and other fluids through a tire innerlinercomposition and elsewhere, for example, from the inside to the outsidesurface of a tire or hose. However, it is also known that nylon can bemoisture sensitive or hygroscopic, the latter term being generallyunderstood to mean that nylon will absorb moisture from the air.Consequently, moisture that may be present in the air contained in apneumatic tire air chamber may be absorbed by the nylon present in atire innerliner construction. The absorbed moisture may thereafterpermeate through the various layers of a tire construction and,possibly, result in a bubble or blister within a layer or between layersthereby making it more susceptible to failure due to separation of thelayers, in order to avoid such failures it is necessary to find a meansof reducing the moisture vapor transmission rate of innerliner and otherair or fluid permeation layers.

U.S. Pat. No. 5,738,158 discloses a pneumatic tire having an airpermeation prevention layer or innerliner layer composed of a thin filmof a resin composition including at least 20% by weight of athermoplastic polyester elastomer comprised of a block copolymer ofpolybutylene terephthalate and polyoxyalkylene diimide diacid at aweight ratio of polybutylene terephthalate/polyoxyalkylene diimidediacid of 85/15 or less. The resin composition can further includedispersed rubber particles wherein the rubber particles have beendynamically vulcanized. The concept of using a resin composition as aninnerliner layer has been further developed, see, e.g., U.S. Pat. No.6,079,465, which describes a pneumatic tire that incorporates such aninnerliner and discloses the use of various thermoplastic resins for usein the composition. This patent also discloses the presence of a tielayer and another layer to promote bond or adhesive strength of theinnerliner layer in the overall structure. The further development ofthis technology to improve adhesion of the innerliner layer in thestructure is described in U.S. Pat. No. 6,062,283 wherein meltviscosities and solubility parameters of thermoplastic resin componentsand elastomer components are controlled according to a specificmathematical formula. This patent also describes a pneumatic tire havingan air permeation preventive layer comprising a low permeabilitythermoplastic elastomer composition comprising a thermoplastic elastomerhaving a thermoplastic resin composition as a continuous phase and arubber composition as a dispersed phase, in which a barrier resincomposition is contained, which low permeability thermoplastic elastomercomposition has a phase structure in which the barrier resin compositionis dispersed in the form of a flat state in the thermoplastic elastomer,is abundant in flexibility, is superior in gas permeation preventiveproperty, and enables the tire to be reduced in weight. The patent alsodescribes the use of a resin film layer to achieve coloration of theinnermost and/or outermost surfaces of the tire.

U.S. Pat. No. 6,136,123 (and its divisional U.S. Pat. No. 6,402,867)describe a process for producing a pneumatic tire using, as an airpermeation preventive layer, a strip-shaped or cylindrical-shapedsingle-layer or multiple-layer thermoplastic film, comprising: applying,to at least a part of the joining portion of the thermoplastic film ortire member facing the thermoplastic film, a tackifier-adhesivecomposition containing a polymer component having an absolute value ofthe difference of the critical surface tension with the rubber componentof the tire member and the polymer component of the surface layer of thethermoplastic film of not more than 6 mN/m, respectively.

Other references of interest include: WO 2004/081107, WO 2004/081106, WO2004/081108, WO 2004/081116, WO 2004/081099, U.S. Pat. Nos. 4,480,074;4,873,288; 5,073,597; 5,157,081; 5,910,544; 6,079,465; 6,346,571;6,538,066; and 6,814,118.

SUMMARY OF THE INVENTION.

One embodiment of the invention relates to a layered constructioncomprising at least three layers, one of which layers comprise a fluidpermeation prevention layer having an upper and a lower surface, atleast one thermoplastic layer in laminate relation with at least saidfluid permeation prevention layer lower surface, said thermoplasticlayer comprising a film-forming semi-crystalline carbon chain polymerhaving a glass transition temperature, Tg, of less than about −20° C.,and said third layer comprising at least one high diene rubber; whereinsaid fluid permeation prevention layer comprises a polymer compositionhaving an air permeation coefficient of 25×10⁻¹² cc·cm/cm² sec cmHg (at30° C.) or less and a Young's modulus of 1 to 500 MPa, said layer ofsaid polymer composition comprising: (A) at least 10% by weight, basedon the total weight of the polymer composition, of at least onethermoplastic resin component having an air permeation coefficient of25×10⁻¹² cc·cm/cm² sec cmHg (at 30° C.) or less and a Young's modulus ofmore than 500 MPa, which resin component is selected from the groupconsisting of polyamide resins, polyester resins, polynitrile resins,polymethacrylate resins, polyvinyl resins, cellulose resins,fluororesins, and imide resins, and (B) at least 10% by weight, based onthe total weight of the polymer composition, of at least one elastomercomponent having an air permeation coefficient of more than 25×10⁻¹²cc·cm/cm² sec cmHg (at 30° C.) and a Young's modulus of not more than500 MPa, which elastomer component is selected from the group consistingof diene rubbers and the hydrogenates thereof, halogen-containingrubbers, silicone rubbers, sulfur-containing rubbers, fluoro-rubbers,hydrin rubbers, acryl rubbers, ionomers and thermoplastic elastomers,the total amount (A)+(B) of the component (A) and the component (B)being not less than 30% by weight based on the total weight of thepolymer composition, wherein the elastomer component (B) is dispersed ina vulcanized state, as a discontinuous phase, in a matrix of thethermoplastic resin component (A) in the polymer composition. Adhesionor bonding of the hydrophobic thermoplastic layer(s) to the layer(s) onwhich they are applied or to which they are in laminate relation, caninclude an adhesive composition or layer in order to improve the bondingbetween such layers, including, bonding of the thermoplastic layer tothe fluid permeation prevention layer and/or the carcass layer of apneumatic tire.

In a preferred aspect, this invention relates to a tire comprising acarcass, an innerliner and a thermoplastic film layer on the surface ofthe innerliner facing the air chamber and where the innerliner comprisesa dynamically vulcanized alloy of an engineering resin and a halogenatedcopolymer of an isoolefin and a para-alkylstyrene, and the thermoplasticfilm comprises a polymer selected from the group consisting of ethylenehomopolymers and copolymers, for example, low density polyethylene. Inanother aspect, the invention relates to a hose comprising the improvedvulcanizable layered construction.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a simplified, partial cross-sectional view of a tire showingthe location of various layers in a tire including a carcass layer, aninnerliner layer and a substantially hydrophobic or moisture vaportransmission resistant layer.

FIG. 1 a is a simplified cross-sectional view of a tire showing thelocation of various layers in a tire including a carcass layer,innerliner layer, a substantially hydrophobic or moisture vaportransmission resistant layer and an adhesive layer between the latterlayer and carcass layer.

FIG. 2 is a simplified cross-sectional view of a tire showing thelocation of various layers in a tire including two substantiallyhydrophobic or moisture vapor transmission resistant layers.

FIG. 2 a is a simplified cross-sectional view of a tire showing thelocation of various layers in a tire including two substantiallyhydrophobic or moisture vapor transmission resistant layers and anadhesive layer between each of the substantially hydrophobic layers andthe surface of the next adjoining layer in which it is in laminatedcontact.

FIG. 2 b is a simplified cross-sectional view of a tire showing thelocation of various layers in a tire including two substantiallyhydrophobic or moisture vapor transmission resistant layers and anadhesive layer between each of the substantially hydrophobic layers andthe surface of the next adjoining layer in which it is in laminatedcontact as well as a further adhesive layer such that both sides of thethermoplastic layer between the carcass and innerliner includes anadhesive layer.

DETAILED DESCRIPTION

In one aspect of the present invention there is provided a solution tothe problem of moisture vapor transmission by using at least one layerof a highly moisture impermeable film as a surface layer on one or moresurfaces of the nylon-containing layer. In another aspect the presentinvention may be useful in tires employing conventional innerlinercompositions based on halogenated isobutylene-containing elastomercomponents and particularly in combination with thermoplasticelastomeric tire innerliner compositions based on vulcanized blends ofengineering resins, e.g., polyamides, and brominatedisobutylene-paramethylstyrene (BIMS) elastomers, produced, for example,using dynamic vulcanization, as disclosed in EP722850B1. In a furtheraspect, among others, the present invention is also useful in otherapplications in which an air or fluid holding layer comprises nylon andtypically where such layer is used in combination with one or more otherlayers, for example, hoses useful for transporting various fluids,including gaseous and liquid as well as mixtures.

For purposes of the present invention, the term “hydrophobic” will beunderstood to be a qualitative term referring to the water-avoidingnature of a material, compound or species; lacking or having a lowaffinity or attraction for water; tending to repel and not absorb water;having a low degree of moisture absorption, tending not to dissolve inor mix with or be wetted by water; having the property of not mixingreadily with water; hydrophobic compounds are typically non-polarcompounds, without charged or electronegative atoms, and often containmany CH bonds. Thus the phrase “substantially hydrophobic” will beunderstood to refer to a matter of degree, tending to be more ratherthan less hydrophobic, generally in the direction of being completelywater repellent or absorbing very low levels of water. Thesedescriptions can be understood to apply to a material, compound,composition, mixture or substance so that one of ordinary skill in theart would understand from these descriptions that both a polyolefin filmand a glass surface are hydrophobic even though measurable levels ofmoisture may be present in the polyolefin and none may be present in theglass. In contrast, nylon is generally understood to be hydrophilic.

As used herein, the new numbering scheme for the Periodic Table Groupsare as disclosed in Chemical and Engineering News, 63 (5), 27 (1985). AHmolecular weights are weight average unless otherwise noted.

Throughout the entire specification, including the claims, the word“comprise” and variations of the word, such as “comprising” and“comprises,” as well as “have,” “having,” “includes,” “include” and“including,” and variations thereof, means that the named steps,elements or materials to which it refers are essential, but other steps,elements or materials may be added and still form a construct with thescope of the claim or disclosure. When recited in describing theinvention and in a claim, it means that the invention and what isclaimed is considered to what follows and potentially more. These terms,particularly when applied to claims, are inclusive or open-ended and donot exclude additional, unrecited elements or methods steps.

In the present context “consisting essentially of” is meant to excludeany element or combination of elements as well as any amount of anyelement or combination of elements that would alter the basic and novelcharacteristics of the invention. Thus, by way of example, a layeredconstruction in which a substantially hydrophilic polymer orsubstantially hydrophilic polymer combination is used to the exclusionof a hydrophobic or substantially hydrophobic polymer combination in alayer, the hydrophobic layer, adjoining the fluid permeation preventionlayer and in which a fluid permeation prevention layer is prepared froma composition other than by dynamically vulcanizing an engineeringresin-containing composition would be excluded. Similarly, and again forexemplary purposes only, a hydrophobic layer containing an amount ofadditive or blend polymer which would alter the moisture vaportransmission rate of the resulting hydrophobic layer or overall layeredstructure to a level not contemplated by the invention would beexcluded.

For purposes of the present invention, unless otherwise defined withrespect to a specific property, characteristic or variable, the term“substantially” as applied to any criteria, such as a property,characteristic or variable, means to meet the sorted criteria in suchmeasure such that one skilled in the art would understand that thebenefit to be achieved, or the condition or property value desired ismet.

Polymer may be used to refer to homopolymers, copolymers, interpolymers,terpolymers, etc. Likewise, a copolymer may refer to a polymercomprising at least two monomers, optionally with other monomers. When apolymer is referred to as comprising a monomer, the monomer is presentin the polymer in the polymerized form of the monomer or in thederivative form the monomer. However, for ease of reference the phrase“comprising the (respective) monomer” or the like is used as shorthand.Isoolefin refers to any olefin monomer having two substitutions on thesame carbon. Multiolefin refers to any monomer having two or more doublebonds. In a preferred embodiment, the multiolefin is any monomercomprising two conjugated double bonds such as a conjugated diene likeisoprene.

Elastomer as used herein, refers to any polymer or composition ofpolymers consistent with the ASTM D1566 definition. The terms may beused interchangeably with the term “rubber(s).”

Alkyl refers to a paraffinic hydrocarbon group which may be derived froman alkane by dropping one or more hydrogens from the formula, such as,for example, a methyl group (CH₃), or an ethyl group (CH₃CH₂), etc.

Aryl refers to a hydrocarbon group that forms a ring structurecharacteristic of aromatic compounds such as, for example, benzene,naphthalene, phenanthrene, anthracene, etc., and typically possessalternate double bonding (“unsaturation”) within its structure. An arylgroup is thus a group derived from an aromatic compound by dropping oneor more hydrogens from the formula such as, for example, phenyl, orC₆H₅.

Substituted refers to at least one hydrogen group by at least onesubstituent selected from, for example, halogen (chlorine, bromine,fluorine, or iodine), amino, nitro, sulfoxy (sulfonate or alkylsulfonate), thiol, alkylthiol, and hydroxy; alkyl, straight or branchedchain having 1 to 20 carbon atoms which includes methyl, ethyl, propyl,tert-butyl, isopropyl, isobutyl, etc.; alkoxy, straight or branchedchain alkoxy having 1 to 20 carbon atoms, and includes, for example,methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, secondarybutoxy, tertiary butoxy, pentyloxy, isopentyloxy, hexyloxy, heptyloxy,octyloxy, nonyloxy, and decyloxy; haloalkyl, which means straight orbranched chain alkyl having 1 to 20 carbon atoms which is substituted byat least one halogen, and includes, for example, chloromethyl,bromomethyl, fluoromethyl, iodomethyl, 2-chloroethyl, 2-bromoethyl,2-fluoroethyl, 3-chloropropyl, 3-bromopropyl, 3-fluoropropyl,4-chlorobutyl, 4-fluorobutyl, dichloromethyl, dibromomethyl,difluoromethyl, diiodomethyl, 2,2-dichloroethyl, 2,2-dibromomethyl,2,2-difluoroethyl, 3,3-dichloropropyl, 3,3-difluoropropyl,4,4-dichlorobutyl, 4,4-difluorobutyl, trichloromethyl,4,4-difluorobutyl, trichloromethyl, trifluoromethyl,2,2,2-trifluoroethyl, 2,3,3-trifluoropropyl, 1,1,2,2-tetrafluoroethyl,and 2,2,3,3-tetrafluoropropyl. Thus, for example, a “substitutedstyrenic unit” includes p-methylstyrene, p-ethylstyrene, etc.

In various preferred embodiments, the present invention is directed to alayered construction comprising at least one layer comprising anengineering thermoplastic resin as a continuous phase and a vulcanizedelastomer as a dispersed phase. Such a composition is prepared, forexample by utilizing technology known as dynamic vulcanization and theresulting composition is known as a dynamically vulcanized alloy (DVA);details of such a composition and its method of preparation aredescribed in detail hereinafter. The construction further comprises anelastomeric composition layer comprising a high diene rubber, forexample, natural rubber and/or styrene butadiene rubber, furtherdescribed hereinafter. Each of these layers typically containsadditional components such as reinforcing agents and process aids, forexample, carbon black and/or exfoliated, intercalated, or simplydispersed clay and rubber processing oil, respectively. The elastomericcomposition layer or high diene rubber-containing layer is typicallyprepared by standard rubber compounding methods, and includescrosslinking agents or curatives, frequently referred to as a curesystem comprising a mixture of two or more individual components, sothat the resulting composition is vulcanizable. On the surface of theengineering thermoplastic resin layer that is adjacent to the fluid thatis being retained by the layered construction, is a hydrophobic filmlayer. Optionally, sandwiched between the elastomeric composition layerand the other surface of the engineering thermoplastic resin layer is asecond hydrophobic film layer. When such an optional second hydrophobiclayer is used, typically there is also used an adhesive composition oradhesive layer between the hydrophobic layer and the elastomericcomposition layer in order to improve interlayer bonding between thesetwo layers. Optionally there is also an adhesive composition or adhesivelayer between the first hydrophobic layer and the engineeringthermoplastic resin layer in order to improve adhesion between theselayers. Typically, the compositions of the two adhesive layers, if bothare present, are the same, although it is not necessary that they be thesame. The engineering resin layer of the present invention can compriseat least one reinforcing filler and other components such that it servesto inhibit the permeation of fluids through it. In the context of itsuse in pneumatic tires, the engineering resin layer serves as a liner,typically at the innermost surface of the tire construction and isreferred to in the tire industry as an innerliner. Its composition andmethod of preparation are designed by one skilled in the art of rubbercompounding to inhibit the passage of air or oxygen through the layer soas to maintain tire pressure over extended periods of time. Avoidance ofpermeation also reduces the chances of interlayer gas pressure buildup,which can lead to premature failure or delamination. The use of at leastone hydrophobic film layer, typically a thermoplastic film, andoptionally two such hydrophobic film layers, significantly inhibits thepermeability of both a fluid such as air and a fluid such as moisturevapor, from the innermost surface of the layered construction through tothe outermost surface of the layered construction and into, for example,the atmosphere. Thus the high air impermeability of an engineering resinsuch as a polyamide or nylon can be supplemented by a hydrophobic filmin order to significantly inhibit the passage or permeation of moisturevapor through such a construction and thereby reduce the chance ofinterlayer failure caused by the volumetric expansion of such vapor.

When the engineering resin layer is used as the innermost layer of ahose construction, it will also inhibit passage of fluids through it.Such fluids can include air, oxygen and other gases, as well as liquidssuch as water, fluorocarbons, or industrial fluids. The nature of thefluid to be contained will dictate the selection of the components ofthe engineering resin-containing layer, including the choice ofvulcanizable rubber used to prepare the DVA composition. Such selectionsare well known to a compounder in the hose industry.

When the engineering resin-containing layer is used as a tireinnerliner, the tire innerliner composition of the present invention maybe used in producing innerliners for motor vehicle tires such as trucktires, bus tires, passenger automobile, motorcycle tires, moped tires,all terrain vehicle tires, and the like. Furthermore, such a layer canbe used in tires intended for non-motorized vehicles such as bicycles.

The first layer is typically a composition comprising a high dienerubber, such as a film or sheet or tire carcass layer. Alternatively,such first layer can be a tubular layer of a hose construction. Thislayer can also comprise reinforcing fibers such as tire cords or othersuitable reinforcement useful in tire applications or hose applications.

If an optional second hydrophobic film layer is not used, then thesecond layer is typically a dynamically vulcanized alloy (DVA)composition as described in detail below and is typically present in theform of a sheet or a film, but may also be present in the form of atubular layer of a hose construction. If the optional second hydrophobicfilm layer is used then the DVA layer is the third layer.

The hydrophobic layer is typically present in the form of a sheet orfilm that is formed, e.g., by the use of extrusion or calendaringprocesses and it is introduced by forming multiple layers in a singleextrusion or calendaring operation.

Halogenated rubber is defined as a rubber having at least about 0.1 mole% halogen, such halogen selected from the group consisting of bromine,chlorine and iodine. Preferred halogenated rubbers useful in thisinvention include halogenated isobutylene-based homopolymers orcopolymers. These polymers can be described as random copolymer of a C₄to C₇ isomonoolefin derived unit, such as isobutylene derived unit, andat least one other polymerizable unit. In one embodiment of theinvention, the halogenated isobutylene-based copolymer is a butyl-typerubber or branched butyl-type rubber, especially brominated versions ofthese elastomers. (Useful unsaturated butyl rubbers such as homopolymersand copolymers of olefins or isoolefins and other types of elastomerssuitable for the invention are well known and are described in RubberTechnology 209-581 (Maurice Morton ed., Chapman & Hall 1995), TheVanderbilt RUBBER Handbook 105-122 (Robert F. Ohm ed., RX VanderbiltCo., Inc. 1990), and Edward Kresge and H. C. Wang in 8 KIRK-OthmerEncyclopedia of Chemical Technology 934-955 (John Wiley & Sons, Inc. 4thed. 1993)).

Butyl rubbers are typically prepared by reacting a mixture of monomers,the mixture having at least (1) a C₄ to C₁₂ isoolefin monomer componentsuch as isobutylene with (2) a multiolefin, monomer component Theisoolefin is in a range from 70 to 99.5 wt % by weight of the totalmonomer mixture in one embodiment, and 85 to 99.5 wt % in anotherembodiment The multiolefin component is present in the monomer mixturefrom 30 to 0.5 wt % in one embodiment and from 15 to 0.5 wt % in anotherembodiment, in yet another embodiment, from 8 to 0.5 wt % of the monomermixture is multiolefin. The isoolefin is preferably a C₄ to C₁₂compound, non-limiting examples of which are compounds such asisobutylene, isobutene, 2-methyl-1-butene, 3-methyl-1-butene,2-methyl-2-butene, 1-butene, 2-butene, methyl vinyl ether, indene,vinyltrimethylsilane, hexene, and 4-methyl-1-pentene. The multiolefin isa C₄ to C₁₄ multiolefin such as isoprene, butadiene,2,3-dimethyl-1,3-butadiene, myrcene, 6,6-dimethyl-fulvene, hexadiene,cyclopentadiene, and piperylene, and other monomers such as disclosed inEP 0 279 456 and U.S. Pat. Nos. 5,506,316 and 5,162,425. Otherpolymerizable monomers such as styrene and dichlorostyrene are alsosuitable for homopolymerization or copolymerization in butyl rubbers.One embodiment of the butyl rubber polymer useful in the invention isobtained by reacting 95 to 99.5 wt % of isobutylene with 0.5 to 8 wt %isoprene, or from 0.5 wt % to 5.0 wt % isoprene in yet anotherembodiment. Butyl rubbers and methods of their production are describedin detail in, for example, U.S. Pat. Nos. 2,356,128, 3,968,076,4,474,924, 4,068,051 and 5,532,312.

Halogenated butyl rubber is produced by the halogenation of the butylrubber product described above. Halogenation can be carried out by anymeans, and the invention is not herein limited by the halogenationprocess. Methods of halogenating polymers such as butyl polymers aredisclosed in U.S. Pat. Nos. 2,631,984, 3,099,644, 4,288,575, 4,554,326,4,632,963, 4,681,921, 4,650,831, 4,384,072, 4,513,116 and 5,681,901. Inone embodiment, the butyl rubber is halogenated in hexane diluent atfrom 4 to 60° C. using bromine (Br₂) or chlorine (Cl₂) as thehalogenation agent. Post-treated halogenated butyl rubber can also beused, as disclosed in U.S. Pat. No. 4,288,575. The halogenated butylrubber typically has a Mooney Viscosity of about 20 to about 70 (ML 1+8at 125° C.); for example, about 25 to about 55 in another embodiment.The halogen content is typically about 0.1 to 10 wt % based on theweight of the halogenated butyl rubber; for example, about 0.5 to 5 wt%; alternatively, about 0.8 to about 2.5 wt %; for example, about 1 toabout 2 wt %.

A commercial embodiment of a halogenated butyl rubber useful in thepresent invention is Bromobutyl 2222 (ExxonMobil Chemical Company). ItsMooney Viscosity is typically about 27 to 37 (ML 1+8 at 125° C., ASTM1646 and its bromine content is about 1.8 to 2.2 wt % relative to theBromobutyl 2222. Furthermore, the cure characteristics of Bromobutyl2222 as provided by the manufacturer are as follows: MH about 28 to 40dN·m, ML is about 7 to 18 dN·m (ASTM D2084). Another commercialembodiment of the halogenated butyl rubber useful in the presentinvention is Bromobutyl 2255 (ExxonMobil Chemical Company). Its MooneyViscosity is about 41 to 51 (ML 1+8 at 125° C., ASTM D1646), and itsbromine content is about 1.8 to 22 wt %. Furthermore, its curecharacteristics as disclosed by the manufacturer are as follows: MH isfrom 34 to 48 dN·m, ML is from 11 to 21 dN·m (ASTM D2084).

Another useful embodiment of halogenated butyl rubber is halogenated,branched or “star-branched” butyl rubber. These rubbers are describedin, for example, EP 0 678 529 B1, U.S. Pat. Nos. 5,182,333 and5,071,913, each incorporated herein by reference. In one embodiment, thestar-branched butyl rubber (“SBB”) is a composition comprising butylrubber and a polydiene or block copolymer. For purposes of the presentinvention, the method of forming the SBB is not a limitation. Thepolydienes, block copolymer, or branching agents (hereinafter“polydienes”), are typically cationically reactive and are presentduring the polymerization of the butyl or halogenated butyl rubber, orcan be blended with the butyl rubber to form the SBB. The branchingagent or polydiene can be any suitable branching agent, and theinvention is not limited to the type of polydiene or branching agentused to make the SBB.

In one embodiment, the SBB is a composition of butyl or halogenatedbutyl rubber as described above and a copolymer of a polydiene and apartially hydrogenated polydiene selected from the group consisting ofstyrene, polybutadiene, polyisoprene, polypiperylene, natural rubber,styrene-butadiene rubber, ethylene-propylene diene rubber (EPDM),ethylene-propylene rubber (EPM), styrene-butadiene-styrene andstyrene-isoprene-styrene block copolymers. Polydienes can be present,based on the total monomer content in wt %, typically greater than 0.3wt %; alternatively, about 0.3 to about 3 wt %; or about 0.4 to 2.7 wt%.

Preferably the branched or “star-branched” butyl rubber used herein ishalogenated. In one embodiment, the halogenated star-branched butylrubber (“HSBB”) comprises a butyl rubber, either halogenated or not, anda polydiene or block copolymer, either halogenated or not. Thehalogenation process is described in detail in U.S. Pat. Nos. 4,074,035,5,071,913, 5,286,804, 5,182,333 and 6,228,978. The present invention isnot limited by the method of forming the HSBB. The polydiene/blockcopolymer, or branching agents (hereinafter “polydienes”), are typicallycationically reactive and are present during the polymerization of thebutyl or halogenated butyl rubber, or can be blended with the butyl orhalogenated butyl rubber to form the HSBB. The branching agent orpolydiene can be any suitable branching agent, and the invention is notlimited by the type of polydiene used to make the HSBB.

In one embodiment the HSBB is typically a composition comprisinghalogenated butyl rubber as described above and a copolymer of apolydiene and a partially hydrogenated polydiene selected from the groupconsisting of styrene, polybutadiene, polyisoprene, polypiperylene,natural rubber, styrene-butadiene rubber, ethylene-propylene dienerubber, styrene-butadiene-styrene and styrene-isoprene-styrene blockcopolymers. Polydienes can be present, based on the total monomercontent in wt %, typically greater than about 0.3 wt %, alternativelyabout 0.3 to 3 wt %, or about 0.4 to 2.7 wt %.

A commercial embodiment of HSBB useful in the present invention isBromobutyl 6222 (ExxonMobil Chemical Company), having a Mooney Viscosity(ML 1+8 at 125° C. ASTM D1646) of about 27 to 37, and a bromine contentof about 22 to 2.6 wt %. Further, cure characteristics of Bromobutyl6222, as disclosed by the manufacturer, are as follows: MH is from 24 to38 dN·m, ML is from 6 to 16 dN·m (ASTM D2084). Preferredisoolefin/para-alkylstyrene copolymers include random copolymerscomprising a C₄ to C₇ isoolefin, such as isobutylene, and ahalomethylstyrene. The halomethylstyrene may be an ortho-, meta-, orpara-alkyl-substituted styrene. In one embodiment, the halomethylstyreneis a halomethylstyrene containing at least 80%, more preferably at least90% by weight of the para-isomer. The “halo” group can be any halogen,desirably chlorine or bromine. The copolymer may also includefunctionalized interpolymers wherein at least some of the alkylsubstituent groups present on the styrene monomer units contain benzylichalogen or another functional group described further below. Theseinterpolymers are herein referred to as “isoolefin copolymers comprisinga halomethylstyrene” or simply “isoolefin copolymer.”

Preferred isoolefin copolymers can include monomers selected from thegroup consisting of isobutylene or isobutene, 2-methyl-1-butene,3-methyl-1-butene, 2-methyl-2-butene, 1-butene, 2-butene, methyl vinylether, indene, vinytrimethylsilane, hexene, and 4-methyl-1-pentene.Preferred isoolefin copolymers may also further comprise multiolefins,preferably a C₄ to C₁₄ multiolefin such as isoprene, butadiene,2,3-dimethyl-1,3-butadiene, myrcene, 6,6-dimethyl-fulvene, hexadiene,cyclopentadiene, and piperylene, and other monomers such as disclosed inEP 279456 and U.S. Pat. Nos. 5,506,316 and 5,162,425. Desirable styrenicmonomers in the isoolefin copolymer include styrene, methylstyrene,chlorostyrene, methoxystyrene, indene and indene derivatives, andcombinations thereof.

Preferred isoolefin copolymers may be characterized as interpolymerscontaining the following monomer units randomly spaced along the polymerchain:

wherein R and R¹ are independently hydrogen, lower alkyl, preferably C₁to C₇ alkyl and primary or secondary alkyl halides and X is a functionalgroup such as halogen. Desirable halogens are chlorine, bromine orcombinations thereof. Preferably R and R¹ are each hydrogen. The —CRR₁Hand —CRR₁X groups can be substituted on the styrene ring in either theortho, meta, or para positions, preferably the para position. Up to 60mole % of the p-substituted styrene present in the interpolymerstructure may be the functionalized structure (2) above in oneembodiment, and in another embodiment from 0.1 to 5 mol %. In yetanother embodiment, the amount of functionalized structure (2) is from0.4 to 1 mol %. The functional group X may be halogen or some otherfunctional group which may be incorporated by nucleophilic substitutionof benzylic halogen with other groups such as carboxylic acids; carboxysalts; carboxy esters, amides and imides; hydroxy; alkoxide; phenoxide;thiolate; thioether; xanthate; cyanide; cyanate; amino and mixturesthereof. These functionalized isomonoolefin copolymers, their method ofpreparation, methods of functionalization, and cure are moreparticularly disclosed in U.S. Pat. No. 5,162,445.

Most useful of such copolymers of isobutylene and p-methylstyrene arethose containing from 0.5 to 20 mole % p-methylstyrene wherein up to 60mole % of the methyl substituent groups present on the benzyl ringcontain a bromine or chlorine atom, preferably a bromine atom(p-bromomethylstyrene), as well as acid or ester functionalized versionsthereof wherein the halogen atom has been displaced by maleic anhydrideor by acrylic or methacrylic acid functionality. These interpolymers aretermed “halogenated poly(isobutylene-co-p-methylstyrene)” or “brominatedpoly(isobutylene-co-p-methylstyrene)”, and are commercially availableunder the name EXXPRO™ Elastomers (ExxonMobil Chemical Company, HoustonTex.). It is understood that the use of the terms “halogenated” or“brominated” are not limited to the method of halogenation of thecopolymer, but merely descriptive of the copolymer which comprises theisobutylene derived units, the p-methylstyrene derived units, and thep-halomethylstyrene derived units.

These functionalized polymers preferably have a substantiallyhomogeneous compositional distribution such that at least 95% by weightof the polymer has a p-alkylstyrene content within 10% of the averagep-alkylstyrene content of the polymer. More preferred polymers are alsocharacterized by a narrow molecular weight distribution (Mw/Mn) of lessthan 5, more preferably less than 2.5, a preferred viscosity averagemolecular weight in the range of about 200,000 to about 2,000,000 and apreferred number average molecular weight in the range of about 25,000to about 750,000 as determined by gel permeation chromatography.

Preferred halogenated poly(isobutylene-co-p-methylstyrene) polymers arebrominated polymers which generally contain from about 0.1 to about 5 wt% of bromomethyl groups. In yet another embodiment, the amount ofbromomethyl groups is about 0.2 to about 2.5 wt %. Expressed anotherway, preferred copolymers contain about 0.05 to about 2.5 mole % ofbromine, based on the weight of the polymer, more preferably about 0.1to about 1.25 mole % bromine, and are substantially free of ring halogenor halogen in the polymer backbone chain. In one embodiment of theinvention, the interpolymer is a copolymer of C₄ to C₇ isomonoolefinderived units, p-methylstyrene derived units and p-halomethylstyrenederived units, wherein the p-halomethylstyrene units are present in theinterpolymer from about 0.4 to about 1 mol % based on the interpolymer.In another embodiment, the p-halomethylstyrene is p-bromomethylstyrene.The Mooney Viscosity (1+8, 125° C., ASTM D1646, modified) is about 30 toabout 60 Mooney units.

In another embodiment, the relationship between the triad fraction of anisoolefin and a p-alkylstyrene and the mol % of p-alkylstyreneincorporated into the copolymer is described by the copolymer sequencedistribution equation described below and is characterized by thecopolymer sequence distribution parameter, m.

F=1−{m A/(1+mA)}

-   -   where: m is the copolymer sequence distribution parameter,    -   A is the molar ratio of p-alkylstyrene to isoolefin in the        copolymer and,    -   F is the p-alkylstyrene-isoolefin-p-alkylstyrene triad fraction        in the copolymer.

The best fit of this equation yields the value of m for copolymerizationof the isoolefin and p-alkylstyrene in a particular diluent. In certainembodiments, m is from less than 38; alternatively, from less than 36;alternatively, from less than 35; and alternatively, from less than 30.In other embodiments, m is from 1-38; alternatively, from 1-36;alternatively, from 1-35; and alternatively from 1-30. Copolymers havingsuch characteristics are disclosed in WO 2004058825 and WO 2004058835.

In another embodiment, the isoolefin/para-alkylstyrene copolymer issubstantially free of long chain branching. For the purposes of thisinvention, a polymer that is substantially free of long chain branchingis defined to be a polymer for which g′_(vis.avg.) is determined to begreater than or equal to 0.978, alternatively, greater than or equal to0.980, alternatively, greater than or equal to 0.985, alternatively,greater than or equal to 0.990, alternatively, greater than or equal to0.995, alternatively, greater than or equal to 0.998, alternatively,greater than or equal to 0,999, as determined by triple detection sizeexclusion chromatography (SEC) as described below. Such polymers arealso disclosed in WO 2004058825 and WO 2004058835.

In another embodiment, the relationship between the triad fraction of anisoolefin and a multiolefin and the mol % of multiolefin incorporatedinto the halogenated rubber copolymer is described by the copolymersequence distribution equation below and is characterized by thecopolymer sequence distribution parameter, m.

F=m A/(1+mA)²

-   -   where: m is the copolymer sequence distribution parameter,    -   A is the molar ratio of multiolefin to isoolefin in the        copolymer and,    -   F is the isoolefin-multiolefin-multiolefin triad fraction in the        copolymer.

Measurement of triad fraction of an isoolefin and a multiolefin and themol % of multiolefin incorporated into the copolymer is described below.The best fit of this equation yields the value of m for copolymerizationof the isoolefin and multiolefin in each diluent. In certainembodiments, m is from greater than 1.5; alternatively, from greaterthan 2.0; alternatively, from greater than 2.5; alternatively, fromgreater than 3.0; and alternatively, from greater than 3.5. In otherembodiments, m is from 1.10 to 1.25; alternatively, from 1.15 to 1.20;alternatively, from 1.15 to 125; and alternatively, m is about 1.20.Halogenated rubbers that have these characteristics are disclosed in WO2004058825 and WO 2004058835.

In another embodiment, the halogenated rubber is substantially free oflong chain branching. For the purposes of this invention, a polymer thatis substantially free of long chain branching is defined to be a polymerfor which g′_(vis.avg.) is determined to be greater than or equal to0.978, alternatively, greater than or equal to 0.980, alternatively,greater than or equal to 0.985, alternatively, greater than or equal to0.990, alternatively, greater than or equal to 0.995, alternatively,greater than or equal to 0.998, alternatively, greater than or equal to0.999, as determined by triple detection SEC as follows. The presence orabsence of long chain branching in the polymers is determined usingtriple detection SEC. Triple detection SEC is performed on a Waters(Milford, Mass.) 150C chromatograph operated at 40° C. equipped aPrecision Detectors (Bellingham, Mass.) PD2040 light scatteringdetector, a Viscotek (Houston, Tex.) Model 150R viscometry detector anda Waters differential refractive index detector (integral with the150C). The detectors are connected in series with the light scatteringdetector being first, the viscometry detector second and thedifferential refractive index detector third. Tetrahydrofuran is used asthe eluent (0.5 ml/min.) with a set of three Polymer Laboratories, Ltd.(Shropshire, United Kingdom) 10 micron mixed-B/LS GPC columns. Theinstrument is calibrated against 16 narrow polystyrene standards(Polymer Laboratories, Ltd.). Data is acquired with TriSEC software(Viscotek) and imported into WaveMetric's Igor Pro program (Lake Oswego,Oreg.) for analysis. Linear polyisobutylene is used to establish therelationship between the intrinsic viscosity [η]_(linear) determined bythe viscometry detector) and the molecular weight (M_(w), determined bythe light scattering detector). The relationship between [η]_(linear)and Mw is expressed by the Mark-Houwink equation.

[η]_(linear)=KM_(w) ^(α)

Parameters K and α are obtained from the double-logarithmic plot ofintrinsic viscosity against M_(w), α is the slope, K the intercept.Significant deviations from the relationship established for the linearstandards indicate the presence of long chain branching. Generally,samples which exhibit more significant deviation from the linearrelationship contain more significant long chain branching. The scalingfactor g′ also indicates deviations from the determined linearrelationship.

[η]_(sample)=g′[η]_(linear)

The value of g′ is defined to be less than or equal to one and greaterthan or equal to zero. When g′ is equal or nearly equal to one, thepolymer is considered to be linear. When g′ is significantly less thanone, the sample is long chain branched. See e.g. E. F. Casassa and G. C.Berry in “Comprehensive Polymer Science,” Vol. 2, (71-120) G. Allen andJ. C. Bevington, Ed., Pergamon Press, New York, 1988. In tripledetection SEC, a g′ is calculated for each data slice of thechromatographic curve. A viscosity average g′ or g′_(vis.avg.) iscalculated across the entire molecular weight distribution. The scalingfactor g′_(vis.avg.) is calculated from the average intrinsic viscosityof the sample.

g′ _(vis.avg.)=[η]_(avg.)/(KM _(w) ^(α).

Other preferred halogenated rubbers include halogenatedisobutylene-p-methylstyrene-isoprene copolymer as described in WO01/21672A1.

The halogenated rubbers useful in the fluid permeation prevention layerand tie layer may be the same or different

For purposes of the present invention, an engineering resin is definedto be any thermoplastic polymer, copolymer or mixture thereof having aYoung's modulus of more than 500 MPa and, preferably, an air permeationcoefficient of less than 60×10⁻¹² cc cm/cm² sec cm Hg (at 30° C.),including, but not limited to, one or more of the following:

a) polyamide resins: nylon 6 (N6), nylon 66 (N66), nylon 46 (N46), nylon11 (N11), nylon 12 (N12), nylon 610 (N610), nylon 612 (N612), nylon 6/66copolymer (N6/66), nylon 6/66/610 (N6/66/610), nylon MXD6 (MXD6), nylon6T (N6T), nylon 6/6T copolymer, nylon 66/PP copolymer, nylon 66/PPScopolymer;

b) polyester resins: polybutylene terephthalate (PBT), polyethyleneterephthalate (PET), polyethylene isophthalate (PEI), PET/PEI copolymer,polyacrylate (PAR), polybutylene naphthalate (PEN), liquid crystalpolyester, polyoxalkylene diimide diacid/polybutyrate terephthalatecopolymer and other aromatic polyesters;

c) polynitrile resins: polyacrylonitrile (PAN), polymethacrylonitrile,acrylonitrile-styrene copolymers (AS), methacrylonitrile-styrenecopolymers, methacrylonitrile-styrene-butadiene copolymers;

d) polymethacrylate resins: polymethyl methacrylate, polyethylacrylate;

e) polyvinyl resins (for illustration, not limitation): vinyl acetate(EVA), polyvinyl alcohol (PVA), vinyl alcohol/ethylene copolymer (EVOA),polyvinylidene chloride (PVDC), polyvinyl chloride (PVC),polyvinyl/polyvinylidene copolymer, polyvinylidene chloride/methacrylatecopolymer;

f) cellulose resins: cellulose acetate, cellulose acetate butyrate;

g) fluorine resins: polyvinylidene fluoride (PVDF), polyvinyl fluoride(PVF), polychlorofluoroethylene (PCTFE), tetrafluoroethylene/ethylenecopolymer (ETFE);

h) polyimide resins: aromatic polyimides);

i) polysulfones;

j) polyacetals;

k) polyactones;

l) polyphenylene oxide and polyphenylene sulfide;

m) styrene-maleic anhydride;

n) aromatic polyketones; and

o) mixtures of any and all of a) through n) inclusive as well asmixtures of any of the illustrative or exemplified engineering resinswithin each of a) through n) inclusive.

For purposes of the present invention, this definition of engineeringresin excludes polymers of olefins, such as polyethylene andpolypropylene.

Preferred engineering resins include polyamide resins and mixturesthereof; particularly preferred resins include Nylon 6, Nylon 66, Nylon6 66 copolymer, Nylon 11, and Nylon 12 and their blends.

High diene content rubber or elastomer, also referred to as high dienemonomer rubber, is a rubber comprising typically at least 50 mole % of aC₄-C₁₂ diene monomer, typically at least about 60 mole % to about 100mole %; more preferably at least about 70 mole % to about 100 mole %;more preferably at least about 80 mole % to about 100 mole %.

Useful high diene monomer rubbers include homopolymers and copolymers ofolefins or isoolefins and multiolefins, or homopolymers of multiolefins.These are well known and are described in Rubber Technology, 179-374(Maurice Morton ed., Chapman & Hall 1995), and The Vanderbilt RubberHandbook 22-80 (Robert F. Ohm ed., R.T. Vanderbilt Co., Inc. 1990).Preferred examples of high diene monomer rubbers include polyisoprene,polybutadiene rubber, styrene-butadiene rubber, natural rubber,chloroprene rubber, acrylonitrile-butadiene rubber and the like, whichmay be used alone or in combination and mixtures.

Another useful group of high diene monomers rubbers includes styrenicblock copolymers such as those having styrene contents of 5 wt. % to 95wt. %, preferably 10 wt. % to 85 wt. %, more preferably 15 wt. % to 70wt. %. Preferred styrenic block copolymers (SBC's) include those thatgenerally comprise a thermoplastic block portion A and an elastomericblock portion B. The block portion A are the hard blocks and are derivedfrom materials which have a sufficiently high glass transitiontemperature to form crystalline or glassy domains at the use temperatureof the polymer. Such hard blocks generally form strong physical“crosslinks” or agglomerates with other hard blocks in the copolymers.The hard block portion, A, generally comprises a polyvinylarene derivedfrom monomers such as styrene, alpha-methyl styrene, other styrenederivatives, or mixtures thereof. The hard block portion A may also be acopolymer derived from styrenic monomers such as those described aboveand olefinic monomers such as ethylene, propylene, butene, isoprene,butadiene, and mixtures thereof. Useful such polymers for the presentinvention typically include less than about 50% glassy phase such thatthe glass transition of the polymer, Tg, should be less than about −50°C.

In one embodiment, the hard block portion A is polystyrene, having anumber-average molecular weight between from about 1,000 to about200,000, preferably from about 2,000 to about 100,000, more preferablyfrom about 5,000 to about 60,000. Typically the hard block portion Acomprises from about 5% to about 80%, preferably from about 10% to about70%, more preferably from about 10% to about 50% of the total weight ofthe copolymer.

The material forming the B-block preferably has a sufficiently low glasstransition temperature at the use temperature of the polymer such thatcrystalline or glassy domains are not formed at these workingtemperatures. The B-block are thus typically regarded as a soft block.The soft block portion B is typically an olefinic polymer derived fromconjugated aliphatic diene monomers of from about 4 to about 6 carbonatoms or linear alkene monomers of from about 2 to about 6 carbon atoms.Suitable diene monomers include butadiene, isoprene, and the like,whereas suitable alkene monomers include ethylene, propylene, butene,and the like, in each instance, mixtures are also suitable. The softblock portion B preferably comprises a substantially amorphouspolyolefin such as ethylenes/propylene polymers, ethylene/butenepolymers, polyisoprene, polybutadiene, and the like or mixtures thereof.The number-average molecular weight of the soft block B is typicallyfrom about 1,000 to about 300,000, preferably from about 10,000 to about200,000, and more preferably from about 20,000 to about 100,000.

Typically the soft block portion B comprises from about 20% to about90%, preferably from about 30% to about 80%, more preferably from about40% to about 80% of the total weight of the copolymer.

Suitable SBC's for use in the compositions described herein include atleast one substantially thermoplastic block portion A and at least onesubstantially elastomeric block portion B. The SBC's may have multipleblocks.

In one embodiment, the SBC's may be an A-B diblock copolymer. In anotherembodiment, the block copolymer may be an A-B-A triblock copolymer. Instill other embodiments, the SBC's may be selected as A-B-A-B tetrablockcopolymers, or A-B-A-B-A pentablock copolymers.

In another embodiment, the SBC's are triblock copolymers having anelastomeric midblock B and thermoplastic endblocks A and A′, wherein Aand A′ may be derived from different vinylarene monomers. In otherembodiments, the SBC's have more than one A block and/or more than one Bblock, wherein each A block may be derived from the same or differentvinylarene monomers and each B block may be derived from the same ordifferent olefinic monomers.

The SBC's may also be radial, having three or more arms, each arm beingan B-A, B-A-B-A, or the like type copolymer and the B blocks being at ornear the center portion of the radial polymer. In other embodiments, theSBC's may have four, five, or six arms.

In one embodiment, the olefinic polymer block comprises at least about50 wt. % of the block copolymer. The unsaturation in olefinic doublebonds may be selectively hydrogenated to reduce sensitivity to oxidativedegradation and such hydrogenation may also have beneficial effects onthe elastomeric properties. For example, a polyisoprene block can beselectively hydrogenated or reduced to form an ethylene-propylene block.In one embodiment, the vinylarene block typically comprises at leastabout 10 percent by weight of the SBC. However, higher vinylarenecontents may be selected for high elastic and low stress relaxationproperties.

Exemplary suitable SBC's for use in for inclusion in the polymericcompositions described herein are styrene-olefin-styrene triblockcopolymers such as styrene-butadiene-styrene (S-B-S),styrene-ethylene/butylene-styrene (S-EB-S),styrene-ethylene/propylene-styrene (S-EP-S), styrene-isoprene-styrene(S-I-S), and mixtures thereof. The SBC may be a selected SBC or a blendof SBC's.

In one embodiment, the SBC's for use in the polymeric compositionsdescribed herein are polystyrene-ethylene/butylene-polystyrene blockcopolymers having a styrene content in excess of about 10 weightpercent. With higher styrene content, the polystyrene block portionsgenerally have a relatively high molecular weight.

In one embodiment, the SBC has a melt flow rate of about 0.01 to about150 dg/min. In another embodiment, the SBC has a melt flow rate of about0.1 to about 100 dg/min. In still another embodiment, the SBC has a meltflow rate of about 1 to about 75 dg/min (each of the melt flow rates asmeasured by ASTM 1238, 2.16 kg and 230° C.).

In one embodiment, the composition includes a SBC comprised of triblocksegments comprised of styrene-derived units and at least one other unitselected from the group consisting of ethylene-derived units,butadiene-derived units, isoprene-derived units, isobutylene-derivedunits and wherein the styrenic block copolymer is comprised of less than20 wt. % of diblock segments. In another embodiment, the compositionincorporates a SBC comprised of segments selected from the groupconsisting of SIS, SBS, SEBS, SEPS, and SIBS(styrene-isoprene-butadiene-styrene) units and wherein from about 5% toabout 95% of diene units in the styrenic block copolymer arehydrogenated.

Exemplary SBC's for use in the polymeric compositions described hereinare commercially available from Dexco Polymers LP under the designationsVector™ and from Kraton Polymers in Houston, Tex. under the designationKraton™.

Generally, polymer compositions, e.g., those used to produce tires, arecrosslinked in the finished tire product. Crosslinking or vulcanizationis accomplished by incorporation of curing agents and/or accelerators;the overall mixture of such agents being typically referred to as a cure“system.” It is known that the physical properties, performancecharacteristics, and durability of vulcanized rubber compounds aredirectly related to the number (crosslink density) and types ofcrosslinks formed during the vulcanization reaction. (See, e.g., Helt etal., The Post Vulcanisation Stabilization for NR, Rubber World 18-23(1991). Curing agents include those components described above thatfacilitate or influence the cure of elastomers, and generally includemetals, accelerators, sulfur, peroxides, and other agents common in theart, and as described above. Crosslinking or curing agents include atleast one of, e.g., sulfur, zinc oxide, and fatty acids and mixturesthereof. Peroxide-containing cure systems may also be used. Generally,polymer compositions may be crosslinked by adding curative agents, forexample sulfur, metal oxides (i.e., zinc oxide, ZnO), organometalliccompounds, radical initiators, etc. and heating the composition ormixture. When the method known as “dynamic vulcanization” is used, theprocess is modified so as to substantially simultaneously mix andvulcanize, or crosslink, at least one of the vulcanizable components ina composition comprising at least one vulcanizable rubber, elastomer orpolymer and at least one elastomer or polymer not vulcanizable using thevulcanizing agent(s) for the at least one vulcanizable component, (See,e.g., U.S. Pat. No. 6,079,465 and the references cited therein). Inparticular, the following are common curatives that can function in thepresent invention: ZnO, CaO, MgO, Al₂O₃, CrO₃, FeO, Fe₂O₃, and NiO.These metal oxides can be used in conjunction with the correspondingmetal stearate complex (e.g., the stearate salts of Zn, Ca, Mg, and Al),or with stearic acid, and either a sulfur compound or an alkylperoxidecompound. (See also, Formulation Design and Curing Characteristics ofNBR Mixes for Seals, RUBBER WORLD 25-30 (1993), To the curative agent(s)there are often added accelerators for the vulcanization of elastomercompositions. The curing agent(s), with or without the use of at leastone accelerator, is often referred to in the art as a curing “system”for the elastomers). A cure system is used because typically more thanone curing agent is employed for beneficial effects, particularly wherea mixture of high diene rubber and a less reactive elastomer is used.

For purposes of dynamic vulcanization in the presence of an engineeringresin to form the highly impermeable layer, any conventional curativesystem which is capable of vulcanizing saturated halogenated polymersmay be used to vulcanize at least the elastomeric halogenated copolymerof a C₄ to C₇ isomonoolefin and a para-alkylstyrene, except thatperoxide curatives are specifically excluded from me practice of thisinvention when the thermoplastic engineering resin(s) chosen are suchthat peroxide would cause these resins themselves to crosslink since theengineering resin would itself vulcanize or crosslink, thereby resultingin an excessively cured, non-thermoplastic composition. Suitablecurative systems for the elastomeric halogenated copolymer component ofthe present invention include zinc oxide in combination with zincstearate or stearic acid and, optionally, one or more of the followingaccelerators or vulcanizing agents: Permalux, thedi-ortho-tolylguanidine salt of dicatechol borate; HVA-2, m-phenylenebis maleimide; Zisnet, 2,4,6-trimercapto-5-triazine; ZDEDC, zinc diethyldithiocarbamate and also including for the purposes of the presentinvention, other dithiocarbamates; Tetrone A, dipentamethylene thiuramhexasulfide; Vultac 5, alkylated phenol disulfide, SP1045, phenolformaldehyde resin; SP1056, brominated alkyl phenol formaldehyde resin;DPPD, diphenyl phenylene diamine; salicylic acid, ortho-hydroxy benzoicacid; wood rosin, abietic acid; and TMTDS, tetramethyl thiuramdisulfide, used in combination with sulfur.

Dynamic vulcanization is conducted at conditions to vulcanize at leastpartially, preferably fully, the elastomeric halogen-containingcopolymer of the air permeation prevention layer.

With reference to the polymers and/or elastomers referred to herein, theterms “cured,” “vulcanized,” or “crosslinked” refer to the chemicalreaction comprising forming bonds as, for example, during chainextension, or crosslinks between polymer chains comprising the polymeror elastomer to the extent that the elastomer undergoing such a processcan provide the necessary functional properties resulting from thecuring reaction when the tire is put to use. For purposes of the presentinvention, absolute completion of such curing reactions is not requiredfor the elastomer-containing composition to be considered “cured,”“vulcanized” or “crosslinked.” For example, for purposes of the presentinvention, a tire comprising the tie layer is sufficiently cured whenthe tire of which it is a component passes the necessary productspecification tests during and after manufacturing and performssatisfactorily when used on a vehicle. Furthermore, the composition issatisfactorily, sufficiently or substantially cured, vulcanized orcrosslinked when the tire can be put to use even if additional curingtime could produce additional crosslinks. With limited experimentationusing known tools and standard techniques, one skilled in the art canreadily determine the appropriate or optimum cure time required for theelastomers) and polymers) selected for use in the tie layer composition,as well as the amount and type of crosslinking agent(s) andaccelerator(s) and the curing temperature that will be used tomanufacture the tire.

Accelerators include amines, guanidines, thioureas, thiazoles, thiurams,sulfonamides, sulfenimides, thiocarbamates, xanthates, and the like.Acceleration of the cure process may be accomplished by adding to thecomposition an amount of the accelerant. The mechanism for acceleratedvulcanization of natural rubber involves complex interactions betweenthe curative, accelerator, activators and polymers. Ideally, all of theavailable curative is consumed in the formation of effective crosslinkswhich join together two polymer chains and enhance the overall strengthof the polymer matrix. Numerous accelerators are known in the art andinclude, but are not limited to, the following: stearic acid, diphenylguanidine (DPG), tetramethylthiuram disulfide (TMTD),4,4′-dithiodimorpholine (DTDM), tetrabutylthiuram disulfide (TBTD),2,2′-benzothiazyl disulfide (MBTS), hexamethylene-1,6-bisthiosulfatedisodium salt dihydrate, 2-(morpholinothio) benzothiazole (MBS or MOR),compositions of 90% MOR and 10% MBTS (MOR 90),N-tertiarybutyl-2-benzothiazole sulfenamide (TBBS), and N-oxydiethylenethiocarbamyl-N-oxydiethylene sulfonamide (OTOS), zinc 2-ethyl hexanoate(ZEH), N,N′-diethyl thiourea. Curatives, accelerators and cure systemsuseful with one or more crosslinkable polymers are well-known in theart.

In one embodiment of the invention, at least one curing agent istypically present at about 0.1 phr to about 15 phr; alternatively atabout 0.5 phr to about 10 phr.

The composition described herein may have one or more filler componentssuch as calcium carbonate, clay, mica, silica and silicates, talc,titanium dioxide, starch and other organic fillers such as wood flour,and carbon black. Suitable filler materials include carbon black such aschannel black, furnace black, thermal black, acetylene black, lamp blackand the like. Reinforcing grade carbon black is most preferred. Thefiller may also include other reinforcing or non-reinforcing materialssuch as silica, clay, calcium carbonate, talc, wollastonite, titaniumdioxide and the like. The filler is normally present in the innerlinerat a level of from about 20 to about 50% by weight of the totalcomposition, more preferably from about 25 to 40% by weight In oneembodiment, the filler is carbon black or modified carbon black. Thepreferred filler is semi-reinforcing grade carbon black, typically usedat a level of about 10 to 150 parts per hundred of rubber, by weight(phr), more preferably about 30 to about 120 phr. Useful grades ofcarbon black as described in Rubber TECHNOLOGY 59-85 (1995) include N110to N990. More desirably, grades of carbon black useful in, for example,tire treads, such as N229, N351, N339, N220, N234 and N110 provided inASTM (D3037, D1510, and D3765) are useful herein. Embodiments of carbonblack useful in, for example, tire sidewalls such as N330, N351, N550,N650, N660, and N762 are particularly useful herein. Embodiments ofcarbon black useful in, for example, innerliners or innertubes, such asN550, N650, N660, N762, N990, and Regal 85 (Cabot Corporation,Alpharetta, Ga.) and the like are similarly particularly useful herein.

Exfoliated, intercalated, or dispersed clays may also be present in thecomposition. These clays, also referred to as “nanoclays”, are wellknown, and their identity, methods of preparation and blending withpolymers is disclosed in, for example, JP 2000109635, JP 2000109605, JP11310643; DE 19726278; WO98/53000; and U.S. Pat. Nos. 5,091,462,4,431,755, 4,472,538, and 5,910,523. Swellable layered clay materialssuitable for the purposes of the present invention include natural orsynthetic phyllosilicatcs, particularly smectic clays such asmontmorillonite, nontronite, beidellite, volkonskoite, laponite,hectorite, saponite, sauconite, magadite, kenyaite, stevensite and thelike, as well as vermiculite, halloysite, aluminate oxides, hydrotalciteand the like. These layered clays generally comprise particlescontaining a plurality of silicate platelets having a thicknesstypically about 4 to about 20 Å in one embodiment, and about 8 to about12 Å in another embodiment, bound together and containing exchangeablecations such as Na⁺, Ca⁺², K⁺ or Mg⁺² present at the interlayersurfaces. Layered clay may be intercalated and exfoliated by treatmentwith organic molecules (swelling agents) capable of undergoing ionexchange reactions with the cations present at the interlayer surfacesof the layered silicate. Suitable swelling agents include cationicsurfactants such as ammonium, alkylamines or alkylammonium (primary,secondary, tertiary and quaternary), phosphonium or sulfoniumderivatives of aliphatic, aromatic or arylaliphatic amines, phosphinesand sulfides. Desirable amine compounds (or the corresponding ammoniumion) are those with the structure R₁R₂R₃N, wherein R₁, R₂, and R₃ are C₁to C₃₀ alkyls or alkenes which may be the same or different. In oneembodiment, the exfoliating agent is a so-called long chain tertiaryamine, wherein at least R₁ is a C₁₂ to C₂₀ alkyl or alkene.

Another class of swelling agents include those which can be covalentlybonded to the interlayer surfaces. These include polysilanes of thestructure −Si(R′)₂R² where R′ is the same or different at eachoccurrence and is selected from alkyl, alkoxy or oxysilane and R₂ is anorganic radical compatible with the matrix polymer of the composite.Other suitable swelling agents include protonated amino acids and saltsthereof containing 2-30 carbon atoms such as 12-aminododecanoic acid,epsilon-caprolactam and like materials. Suitable swelling agents andprocesses for intercalating layered silicates are disclosed in U.S. Pat.Nos. 4,472,538, 4,810,734, 4,889,885 and WO92/02582.

In a preferred embodiment of the invention, the exfoliating or swellingagent is combined with a halogenated polymer. In one embodiment theagent includes all primary, secondary and tertiary amines andphosphines; alkyl and aryl sulfides and thiols; and their polyfunctionalversions. Desirable additives include: long-chain tertiary amines suchas N,N-dimethyl-octadecylamine, N,N-dioctadecyl-methylamine,dihydrogenated tallowalkyl-methylamine and the like, andamine-terminated polytetrahydrofuran; long-chain thiol and thiosulfatecompounds such as hexamethylene sodium thiosulfate. In anotherembodiment of the invention, improved interpolymer impermeability isachieved by the use of polyfunctional curatives such as hexamethylenebis(sodium thiosulfate) and hexamethylene bis(cinnamaldehyde).

The amount of exfoliated, intercalated, or dispersed clay incorporatedin the composition in accordance with this invention is an amountsufficient to develop an improvement in the mechanical properties orbarrier properties of the composition, e.g. tensile strength orair/oxygen permeability. Amounts typically can be from about 0.5 wt % toabout 15 wt % in one embodiment, or about 1 wt % to about 10 wt % inanother embodiment, and about 1 wt % to about 5 wt % in yet anotherembodiment, based on the polymer content of the composition. Expressedin parts per hundred rubber, the exfoliated, intercalated, or dispersedclay may be present at about 1 phr to about 30 phr in one embodiment,and about 3 phr to about 20 phr in another embodiment. In oneembodiment, the exfoliating clay is an alkylamine-exfoliating clay.

As used herein, the term “process oil” means both the petroleum derivedprocess oils, synthetic plasticizers and reactive plasticizers. Aprocess or plasticizer oil may be present in air barrier compositions,but the amount of such materials is limited because they tend to detractfrom the fluid permeation prevention properties of the composition. Theoils or plasticizers are primarily used to improve the processing of thecomposition during preparation of the layer, e.g., mixing, calendaring,etc. Generally suitable plasticizer oils include aliphatic acid estersor hydrocarbon plasticizer oils such as paraffinic or naphthenicpetroleum oils. In addition, plasticizers such as organic esters andother synthetic plasticizers can be used. A particularly preferredplasticizer for use in a DVA composition is N-butylsulfonamide or otherplasticizers suitable for polyamides. In another embodiment, rubberprocess oils such as naphthenic, aromatic or paraffinic extender oilsmay be present at about 1 phr to about 5 phr. Alternatively, thedynamically vulcanized fluid barrier compositions of the presentinvention can include a reactive softener or plasticizer. Such materialsare typically based on maleated ethylene ethyl acrylate (EEA); maleatedethylene oxide (EO) and maleated ethylene propylene (EP) copolymers(such as Exxelor brand from ExxonMobil Chemical Company); ethyleneacrylic ester terpolymers based on methyl-, ethyl- or butyl-acrylate andthe third monomer, either maleic anhydride or glycidyl methacrylate(Lotader brand from Arkema, Inc.); and other epoxidized polymers arealso useful, such as epoxidized natural rubber and epoxidizedstyrene-butadiene-styrene (SBS) terpolymers. In still anotherembodiment, naphthenic, aliphatic, paraffinic and other aromatic oilsare substantially absent from the composition. By “substantiallyabsent”, it is meant that naphthenic, aliphatic, paraffinic and otheraromatic oils may be present, if at all, to an extent no greater than 2phr in the composition.

The term “dynamic vulcanization” is used herein to denote avulcanization process in which the engineering resin and the rubber aremixed under conditions of high shear and elevated temperature in thepresence of a curing agent. As a result, the rubber is simultaneouslycrosslinked and dispersed as fine particles, for example, in the form ofa microgel, within the engineering resin which forms a continuousmatrix; the resulting composition is known in the art as a “dynamicallyvulcanized alloy” or DVA. Dynamic vulcanization is effected by mixingthe ingredients at a temperature which is at or above the curingtemperature of the rubber using in the equipment such as roll mills,Banbury(r) mixers, continuous mixers, kneaders, or mixing extruders(such as twin screw extruders). The unique characteristic of thedynamically cured composition is that, notwithstanding the fact that therubber is cured, the composition can be processed and reprocessed byconventional thermoplastic processing techniques such as extrusion,injection molding, compression molding, etc. Scrap and or flashing canalso be salvaged and reprocessed.

The dynamic vulcanization process is conducted at conditions tovulcanize at least partially, preferably folly, the elastomerichalogen-containing copolymer. To accomplish this, the thermoplasticengineering resin, the elastomeric copolymer and optional otherpolymers, are mixed together at a temperature sufficient to soften theresin or, more commonly, at a temperature above its melting point whenthe resin is crystalline. Preferably the cure system is premixed in theelastomer component. Heating and masticating at vulcanizationtemperatures are generally adequate to complete vulcanization in about0.5 to about 10 minutes. The vulcanization time can be reduced byelevating the temperature of vulcanization. A suitable range ofvulcanization temperatures is typically from about the melting point ofthe resin to about 300° C.; for example, the temperature may range fromabout the melting point of the matrix resin to about 275° C. Preferablythe vulcanization is carried out at a temperature range from about 10°C. to about 50° C. above the melting temperature of the matrix resin.

It is preferred that the mixing process be continued until the desiredlevel of vulcanization or crosslinking is completed. If vulcanization ispermitted to continue after mixing has stopped, the composition may notbe reprocessable as a thermoplastic. However, dynamic vulcanization canbe carried out in stages. For example, vulcanization can be commenced ina twin screw extruder and pellets formed of the DVA material or materialusing an underwater pelletizer, thereby quenching the vulcanizationbefore it is completed. The vulcanization process can be completed at alater time under dynamic vulcanization conditions. Those skilled in theart will appreciate the appropriate quantities, types of curatives andextent of mixing time required to carry out the vulcanization of therubber. Where necessary or desirable to establish the appropriateconcentrations and conditions, the rubber alone can be vulcanized usingvarying amounts of curative, which may include one or more curativesand/or accelerators, to determine the optimum cure system to be utilizedand the appropriate cure conditions to achieve a substantially fullcure. While it is preferred that all components be present in themixture prior to carrying out the dynamic vulcanization process, this isnot a necessary condition. For example, in one embodiment, the elastomerto be cured can be dynamically vulcanized in the presence of a portionor all of the thermoplastic engineering resin. This blend can then belet down, or dispersed under suitable conditions into additionalthermoplastic engineering resin. Similarly, it is not necessary to addall of the fillers and oil, when used, prior to the dynamicvulcanization stage. A portion or all of the fillers and oil can beadded after the vulcanization is completed. Certain ingredients, such asstabilizers and process aids function more effectively if they are addedafter curing.

In an alternative embodiment, the dynamic vulcanization process isconducted according to the technology and method disclosed inPCT/US2005/38824, filed Oct. 27, 2005, entitled “Thermoplastic ElastomerComposition and Process for Producing Same,” hereby incorporated byreference. When such technology is used it is possible to achieve adynamically vulcanized composition in which the small vulcanizedparticles formed by dynamic vulcanization comprise greater than about 60volume % of the volume of the elastomer and engineering resincomposition. The unusually high concentration is achieved by utilizing afractional, staged addition sequence of the halogenated elastomercomponents) during the dynamic vulcanization process, as described inthe application.

The degree of cure of the vulcanized rubber can be described in terms ofgel content, cross-link density, the amount of extractable components orit can be based on the state of cure that would be achieved in therubber were it to be cured in the absence of the resin. For example, intitle present invention, it is preferred that the halogenated elastomerachieve about 50 to about 85% of full cure based on the elastomer per seas measured, e.g., by tensile strength or using the oscillating disccure meter test (ASTM D 2084, Standard Test Method for RubberProperty-Vulcanization Using Oscillating Disk Cure Meter).

Typically, the hydrophobic, or substantially hydrophobic, layercomprises a thermoplastic polymer or copolymer that substantiallyresists water absorption. For convenience, this layer is also referredto herein as the thermoplastic layer. Useful or suitable materials forthis layer are also described as semi-crystalline carbon chain polymersor copolymers, including blends of such polymers and copolymers. Thesemi-crystalline character of the polymer provides for its ability to beformed into a film which is preferred in the present application. Itscarbon chain character contributes to its substantially hydrophobicproperty. Such carbon chain polymers include polymers and copolymersknown to those skilled in the art as polyolefins, styrenics, vinyls,acrylics, fluorocarbons, and diene polymers. The preferred polymersshould have an equilibrium water content at 100% relative humidity ofless than about 0.1 g per 100 g polymer or a molar water content perstructural unit under the same conditions of less than about 0.1.Various polymers are suitable for use in the present invention, thosetypically useful include polyolefins such as ethylene homopolymers andcopolymers, for example, as low density polyethylene (LDPE), linear lowdensity polyethylene (LLDPE), high density polyethylene (HDPE),ethylene-alpha olefin copolymers wherein the alpha olefin includes oneto about eight carbon atoms, including, but not limited to,ethylene-styrene, ethylene-propylene, ethylene-butene, ethylene-hexene,ethylene-octene, and the like. Useful polymers can be suggested by acombination of properties, as noted, and further by using theinformation provided in D. W. Van Krevelen, “Properties of Polymers,”3^(rd) edition, Elsevier (1990), pages 569-572, incorporated herein byreference (referred to as “Van Krevelen”). Generally, as described inthe reference, polymers characterized as hydrophobic typically obeyHenry's Law over the complete range of relative pressures and onlyminute quantities of water are sorbed. Various useful polymers andcopolymers include those having structural groups, individually and incombination, and molar water contents as illustrated and summarized inTable 18.11 of Van Krevelen. In other words, the suitability of polymershaving different structural groups can be estimated based on the data inthe cited Table. Furthermore, polymers useful in the present inventionshould be suitably flexible under ambient conditions of use of thearticle in which they are used, for example a pneumatic tire, a hose,etc. Such polymers exhibit a glass transition (Tg) of less than about−20° C., preferably less than about −30° C., most preferably less thanabout −40° C. In selecting useful polymers one can use a combination ofpreferred levels of water content as described above and Tg. In anotherembodiment, useful polymers have an Melt Index (ASTM 1238, condition E)of 01. to 200 dg/mm, preferably 0.5 to 150 dg/min. In anotherembodiment, useful polymers have an elongation to break of greater 500%,preferably greater than 600%, preferably greater than 650%, as measuredby ASTM D-882. In another embodiment, preferred polymers includepolyethylene homo and copolymers having a density of 0.900 to 0.96 g/cc,preferably 0.910 to 0.95 g/cc as measured by ASTM-D1505. In anotherembodiment, preferred polymers include polyethylene homo and copolymershaving a melt strength of 2 cN or more, preferably 3 to 100 cN,preferably 4 to 50 cN, preferably 5c N or more. Melt Strength ismeasured using a Goettfert Rheotens attached to an Instron capillaryrheometer. The polymer melt is extruded through a capillary with aradius of 0.007633 cm and an aspect ratio (capillary length/capillaryradius) of 33.531 at a constant plunger velocity. Therefore, the polymermelt is subjected to a constant apparent wall shear rate. The extrudedmelt is subsequently stretched by a pair of serrated wheels having radiiof 1.91 cm at a distance (H) from the capillary exit. The rotationalspeed of the wheels is increased linearly with time while the draw downforce (F) is monitored. Melt strength is reported as the draw down force(cN) when the strand breaks. The following conditions are used in themelt strength measurements: Temperature=190° C., Plunger speed=0.127cm/s, wheel acceleration=2.4 cm/s/s, capillary radius=0.076327 cm,capillary length=2.5593 cm, barrel radius=0.47625 cm, and wheelradius=1.91 cm. The thermoplastic, substantially hydrophobic layerthickness is typically about 1 micron to about 100 microns; preferablyabout 1 micron to about 50 microns; or about 1 micron to about 40microns; for example, about 5 microns to about 35 microns or about 25microns. Preferably this layer is as thin as can reasonably be processedconsistent with achieving the desired or target properties of thefinished tire construction. For purposes of the present invention,suitable thermoplastic materials can be identified by measuring themoisture vapor transmission rate (MVTR) of the thermoplastic materialbeing considered and especially that of a layered construction employingsuch thermoplastic material. A significant reduction in the MVTR of aconstruction employing one or more layers of the thermoplastic materialin or as one of the layers will indicate that such a material issuitable. Naturally, the thickness of the thermoplastic material willaffect the level of reduction and a balance can be struck between animprovement in MVTR and maintenance of other physical and dynamicproperties necessary for the sound functioning of the article in whichsuch layer(s) is or are incorporated, including, for example, interlayerbond strength, dynamic storage modulus, thermal stability at high andlow temperatures, etc. Typically, the MVTR will be about 25% lower thana construction without such a layer; preferably about 30% lower; morepreferably about 35% lower; still more preferably about 45% lower; forexample, the MVTR can be about 50% lower or more. In a constructionemploying multiple layers of a substantially hydrophobic thermoplasticfilm, MVTR can be reduced even further; for example, about 50%, 60%, 70%lower or more. Reduction in MVTR can also encompass values in a rangerepresented by the figures recited as well as intermediate values; forexample, 25%-70%; 25%-60%; 30%-50%; 35%-60%; 30%-65%; 33%-55%; etc.Furthermore, the thermoplastic material, for example low densitypolyethylene, optionally can include other additives or fillers,preferably to further reduce permeability, including, for example,carbon black, calcium carbonate, talc, clay and mixtures thereof. Usefulamounts of such supplemental additives are typically about 5 phr toabout 60 phr; preferably about 10 phr to about 50 phr; but in eachinstance where such optional material is included, its concentration islimited to the amount that does not significantly adversely affectelongation to break of the resulting mixture. In other words, theresulting modified thermoplastic material must meet processsatisfactorily and achieve acceptable or suitable properties in acomposite structure in use.

Further optional, useful additives for use in the fluid permeationprevention layer are typically added at a level of less than about 10phr and can be selected from the group consisting of pigments,antioxidants, antiozonants, processing aids, tackifiers, and the likeand mixtures thereof. Such optional additives can be included at thediscretion of the skilled compounder in order to achieve a particularadvantage in the composition, e.g., the use of a tackifier to improvecontact adhesion during tire building or an antioxidant to improve heataging characteristics of the cured composition, provided that theessential properties of the composition are not unnecessarilycompromised, e.g., impermeability.

Various alternative methods for forming and applying the plastic layers)and the adhesive layers) to the other layers can be used as is wellknown in the art. For example, various useful plastic shaping methodsare described in S. Middleman, “Fundamentals of Polymer Processing,”particularly Chapters 6-8, and 10, McGraw-Hill, New York, 1977; Z.Tadmor and C. G. Gogos, “Principles of Polymer Processing,” John Wiley &Sons, New York, 1979, Part IV (Shaping), incorporated by reference. Inparticular, the hydrophobic composition can be formed into a layersuitable for the end use application, using, for example, an extruder ora calendar. Where convenient or useful, extrusion can include the use ofequipment allowing for the dual or multiple extrusion of the fluidpermeation prevention layer, the hydrophobic layer or multiplehydrophobic layers as discussed herein, an adhesive layer where used,and the high diene rubber layer, for example, a tire carcass layer. In apreferred embodiment, the hydrophobic layer is prepared for use in atire construction and has a thickness that is typically about 5 mm orless; preferably about 2.5 mm or less; more preferably about 0.2 toabout 2.0 mm; most preferably about 0.2 to about 1.5 mm; for exampleabout 0.3 to about 0.9 mm. The thickness of the hydrophobic layer foruse in a hose construction can be the same or different depending on theapplication in which the hose will be employed. For example, anunreinforced, low pressure hose can have different performancerequirements than a high pressure, reinforced hose and, similarly, ahose intended for use with a liquid can differ from one for use with agas. Adjustment of the thickness is within the skill of the productdesigner, engineer or chemist, based, if necessary, on limitedexperimentation.

The dynamically vulcanized fluid permeation prevention layer or thehydrophobic layer that is intended to be in contact with the innersurface of the carcass layer of a tire or with the inner surface of atubular hose structure should exhibit sufficient bonding in order toavoid delamination or failure of the bond between the layers. The sameis true of the hydrophobic layer that is laminated to or intended to bein contact with the fluid permeation prevention layer. While thedynamically vulcanized composition of the fluid permeation preventionlayer may ordinarily exhibit sufficient bond strength to the carcasslayer or inner hose surface, the hydrophobic layer(s) are less likely toexhibit sufficient adhesion to the layers to which they are laminated.Thus, while it is optional, it is useful, alternatively it is preferred,to include a layer or composition to improve adhesion between thesecomponents. The optional layer or composition is referred to as anadhesive layer that, in a pneumatic tire for example, is typicallysituated between the innerliner layer, with or without a hydrophobiclayer, and the inside surface of the carcass layer. One or more adhesivelayers can be included in order to further improve interlayer adhesionbetween various layers, as described. When present on the inner surfaceof the tire carcass or the inner surface of a tubular hose structure,the adhesive layer is typically about 1 micron to about 100 microns inthickness; preferably about 5 microns to about 50 microns; or about 10microns to about 40 microns; for example, about 20 microns to about 35microns or about 25 microns. When an adhesive layer is used between thefluid permeation prevention layer and a hydrophobic layer closest to thefluid, its thickness can be the same as recited above or, alternatively,somewhat thinner; typically about 0.5 microns to about 15 microns;alternatively about 0.5 microns to, about 5 microns. The adhesive layeris conveniently formed by co-extrusion with the innerliner layer so thatthe two layers can then be contacted with the carcass layer; if twoadhesive layers are used, both can be co-extruded with the innerlinerlayer. Alternatively, the adhesive layer can be independently prepared,stored between release sheets and used as needed or it can be formed asa fluid composition and sprayed or brushed on the surface(s) where andwhen needed; combinations of these techniques can be used. The adhesivelayer comprises at least one polymer, copolymer, chemically modifiedpolymers or copolymers and mixtures thereof as well as other additivescommonly employed in adhesive compositions. Typical components useful inadhesive compositions include one or more tackifier, curatives, anelastomer component that is co-vulcanizable with diene rubbers, anelastomer component that is co-vulcanizable with nylon or otherthermoplastic matrix employed with the innerliner composition, andothers well-known to those skilled in the art of rubber, andparticularly tire, compounding. Particularly useful polymers includestyrene butadiene styrene copolymers (SBS) and epoxidized SBS such asEpofriend brand series of copolymers from Daicel Chemical.Alternatively, the adhesive composition comprises maleated ethylenecopolymer, epoxidized ethylene polymers, such as ethylene acrylic esterterpolymers based on methyl-, ethyl- or butyl-acrylate and a thirdmonomer, such as maleic anhydride or glycidyl methacrylate (Lotaderbrand from Arkema, Inc.; polymers of this type can be particularlyuseful between a hydrophobic layer comprising an ethylene homopolymer orcopolymer such as LDPE and the dynamically vulcanized fluid permeationprevention layer comprising nylon, since the epoxidized ethylene polymercomprises a terpolymer, including maleic anhydride or epoxy species andethylene species). Such a polymer has been used for preparing anadhesive composition layer between ethylene homopolymers or copolymers,such as polyethylene, and polar polymers, such as nylon and polyester.Also useful are ethylene ionomers (such as ethylene acrylic acid andvarious metal counter ions), ethylene acrylate copolymers, and ethylenevinyl acetate copolymers. Useful adhesive compositions can be preparedas described, for example, in WO 96/34736 or U.S. Pat. No. 6,402,867,incorporated herein by reference in their entirety.

The compositions of the present invention and layered structures formedusing such compositions can be used in tire applications; tire curingbladders; air sleeves, such as air shock absorbers, diaphragms; and hoseapplications, including gas and fluid transporting hoses. Thecompositions and hydrophobic layers) comprising such compositions andconstructions are particularly useful in pneumatic tires to resistmoisture vapor transmission, to improve air holding qualities of theoverall tire innerliner construction and to improve the stability of theresulting multilayer tire construction. An especially usefulconstruction is one in which a hydrophobic film layer is joined to thetire innerliner layer and the hydrophobic layer forms the innermostsurface of the tire and the opposite innerliner layer surface is incontact with and adhered to the inner surface of the tire carcass.Alternatively, where a second hydrophobic layer is used on the oppositeinnerliner surface layer an adhesive layer can be used between thatsecond hydrophobic layer and the inner tire carcass layer in order tofurther enhance adhesion of these two dissimilar components. As is wellknown, the carcass layer typically comprises reinforcing tire cords. Asdiscussed in detail above, the innerliner layer exhibits advantageouslylow permeability properties and preferably comprises a dynamicallyvulcanized composition comprising an engineering resin, particularlypolyamide, and a halogenated isobutylene-paramethyl styrene copolymer.Furthermore, as a consequence of the unique physical properties of thehydrophobic layer, it can be a very thin layer, thereby resulting in anoverall structure for a tire construction (as well as otherconstructions comprising an air or fluid holding layer and hydrophobiclayer) having reduced weight Such weight savings, particularly in a tireconstruction or a hose of significant length, can be substantial.

Forming a tire is a complex, multi-step process that utilizes severaldifferent components or layers. Typically the innerliner layer or“stock” is prepared by calendaring the compounded innerliner rubbercomposition prepared as described above into a sheet form having athickness of about 0.5 mm to about 2 mm and cutting the sheet intostrips of appropriate width and length for innerliner application in aparticular size or type tire. The innerliner is then ready for use as anelement in the construction of a pneumatic tire. The pneumatic tire iscomprised of a multilayered laminate comprising an outer surface whichincludes the tread and sidewall elements, an intermediate carcass layerwhich comprises a number of plies containing tire reinforcing fibers,(e.g., rayon, polyester, nylon or metal fibers) embedded in a rubberymatrix, and an innerliner layer which is laminated to the inner surfaceof the carcass layer. Tires are normally built on a tire forming drumusing the layers described above. After tine uncured tire has been builton the drum, it is removed and placed in a heated mold. The moldcontains an inflatable tire shaping bladder that is situated within theinner circumference of the uncured tire. After the mold is closed thebladder is inflated and it shapes the tire by forcing it against theinner surfaces of the closed mold during the early stages of the curingprocess. The heat within the bladder and mold raises the temperature ofthe tire to vulcanization temperatures. Vulcanization temperatures aretypically about 100° C. to about 250° C.; preferably about 150° C. toabout 200° C. Cure time may vary from about one minute to several hours;preferably from about 5 to 30 minutes. Cure time and temperature dependon many variables well known in the art, including the composition ofthe tire components, including the cure systems in each of the layers,the overall tire size and thickness, etc. Vulcanization parameters canbe established with the assistance of various well-known laboratory testmethods, including the test procedure described in ASTM D 2084 (StandardTest Method for Rubber Property-Vulcanization Using Oscillating DiskCure Meter) as well as stress-strain testing, adhesion testing, flextesting, etc. Vulcanization of the assembled tire results in complete orsubstantially complete vulcanization or crosslinking of all elements orlayers of the tire assembly, i.e., the innerliner, the carcass and theouter tread and sidewall layers. In addition to developing the desiredstrength characteristics of each layer and the overall structure,vulcanization enhances adhesion between these elements, resulting in acured, unitary tire from what were separate, multiple layers.

FIG. 1 is a partial cross-sectional view along the meridian direction ofa tire illustrating a typical example of the arrangement of an airpermeation prevention or innerliner layer of a pneumatic tire and asubstantially hydrophobic thermoplastic layer. In FIG. 1, a portion ofthe tread is indicated at 1, a carcass layer 2 is indicated at 2 and thetire sidewall is indicated at 4. On the tire inner surface, inside ofthe carcass layer 2 there is provided an innerliner layer 3. On theinnermost surface of the innerliner layer is the substantiallyhydrophobic thermoplastic layer 5 of the present invention. FIG. 1 aillustrates the same construction as shown in FIG. 1 except that anadhesive layer 6 is included between layer 3, the innerliner, and layer2, the carcass.

FIG. 2 is a similar partial cross-sectional view along the meridiandirection of a tire illustrating a typical example of the arrangement ofan air permeation prevention or innerliner layer of a pneumatic tire,further illustrating an alternative embodiment of the present invention.In FIG. 2, the tread portion 1, carcass layer 2 and sidewall 4 are asillustrated in FIG. 1. Once again on the tire inner surface, inside ofthe carcass layer 2 there is provided an innerliner layer 3. On theinnermost surface of the innerliner layer as well as on the oppositesurface of the innerliner layer are substantially hydrophobicthermoplastic layers 5 and 5′ of the present invention. FIG. 2 aillustrates incorporation of optional adhesive layer 6 between layer 5and layer 3 as well as optional adhesive layer 6′ between layer 5′ andlayer 2 (carcass); As illustrated in the further alternative embodiment,FIG. 2 b, adhesive layer 6 is included between layer 5 and layer 3,adhesive layer 7 is included between layer 5′ and layer 3, and adhesivelayer 8 is included between layer 5′ and layer 2. In other words, anadhesive layer is included on both surfaces of substantially hydrophobiclayer 5′ so that it is well bonded to both of the surfaces that itcontacts, innerliner layer 3 and the carcass layer 2.

As used throughout the specification and claims, including the describedembodiments, the singular forms “a,” an,” and “the” include pluralreferents unless the context clearly dictates otherwise. Thus, forexample, reference to “a thermoplastic polymer for use in thehydrophobic layer” includes a single thermoplastic as well a two or moredifferent thermoplastics in combination or admixture, and the like.

In the specification and claims the term “about” when used as a modifierfor, or in conjunction with, a variable, characteristic or condition isintended to convey that the numbers, ranges, characteristics andconditions disclosed herein are flexible and that practice of thepresent invention by those skilled in the art using temperatures,concentrations, amounts, contents, carbon numbers, properties such aspurity, particle size, surface area, bulk density, etc., that areoutside of the range or different from a single value, will achieve thedesired result, namely, a multilayer construction comprising ahydrophobic layer, where such multilayer construction is suitable foruse in an article of manufacture useful for containing a fluid,including, for example, a pneumatic tire, a hose, etc.

The following examples are provided as specific illustrations ofembodiments of the claimed invention. It should be understood, however,that the invention is not limited to the specific details set forth inthe examples. All parts and percentages in the examples, as well as inthe specification, are by weight unless otherwise specified. Any rangeof numbers recited in the specification or claims, such as thatrepresenting a particular set of properties, units of measure,conditions, physical states or percentages, is intended to literallyincorporate expressly herein by reference or otherwise, any numberfalling within such range, including any subset of numbers within anyrange so recited. For example, whenever a numerical range with a lowerlimit, R_(L), and an upper limit R_(U), is disclosed, any number Rfalling within the range is specifically disclosed. In particular, thefollowing numbers R within the range are specifically disclosed:R=R_(L)+k(R_(U)−R_(L)), where k is a variable ranging from 1% to 100%with a 1% increment, e.g., k is 1%, 2%, 3%, 4%, 5% . . . 50%, 51%, 52% .. . 95%, 96%, 97%, 98%, 99%, or 100%. Moreover, any numerical rangerepresented by any two values of R, as calculated above is alsospecifically disclosed.

Various aspects or embodiments of the present invention are set forth inthe following enumerated paragraphs:

1. A layered construction comprising at least three layers, one of whichlayers comprising:

1) a fluid permeation prevention layer having an upper and a lowersurface;

2) at least one thermoplastic layer in laminate relation with the fluidpermeation prevention layer lower surface, said thermoplastic layercomprising a film-forming semi-crystalline carbon chain polymer having aglass transition temperature, Tg, of less than about −20° C.; and

3) a layer comprising at least one high diene rubber,

wherein said fluid permeation prevention layer comprises a polymercomposition having an air permeation coefficient of 25×10⁻¹² cc·cm/cm²sec cmHg (at 30° C.) or less and a Young's modulus of 1 to 500 MPa,where said polymer composition comprises:

-   -   (A) at least 10% by weight, based on the total weight of the        polymer composition, of at least one thermoplastic resin        component having an air permeation coefficient of 25×10⁻¹²        cc·cm/cm² sec cmHg (at 30° C.) or less and a Young's modulus of        more than 500 MPa, which resin component is an engineering resin        and or is selected from the group consisting of polyamide        resins, polyester resins, polynitrile resins, polymethacrylate        resins, polyvinyl resins, cellulose resins, fluororesins, and        imide resins, and    -   (B) at least 10% by weight, based on the total weight of the        polymer composition, of at least one elastomer component having        an air permeation Coefficient of more than 25×10⁻¹² cc·cm/cm²        sec cmHg (at 30° C.) and a Young's modulus of not more than 500        MPa, which elastomer component is selected from the group        consisting of diene rubbers and the hydrogenates thereof,        halogen-containing rubbers, silicone rubbers, sulfur-containing        rubbers, fluoro-rubbers, hydrin rubbers, acryl rubbers, ionomers        and thermoplastic elastomers, the total amount (A)+(B) of the        component (A) and the component (B) being not less than 30% by        weight based on the total weight of the polymer composition,        wherein the elastomer component (B) is dispersed in a vulcanized        state, as a discontinuous phase, in a matrix of the        thermoplastic resin component (A) in the polymer composition.

2. The construction of paragraph 1 wherein said thermoplastic polymerhas an equilibrium water content at 100% relative humidity of less thanabout 0.1 g per 100 g polymer or a molar water content per polymerstructural unit of less than about 0.1.

3. The construction of paragraph 1 or 2 further comprising a secondthermoplastic layer, the thermoplastic of said second thermoplasticlayer being the same or different from said first thermoplastic layerand wherein said second thermoplastic layer is in laminate relation withthe other of said upper and lower surfaces of said fluid permeationprevention layer.

4. The construction of paragraph 1, 2 or 3 wherein: (1) when saidconstruction comprises one thermoplastic layer, said surface of saidfluid permeation prevention layer not in contact with said thermoplasticlayer further comprises an adhesive composition; and (2) when saidconstruction comprises two thermoplastic layers each having surfaces, asurface of one of said thermoplastic layers not in contact with saidfluid permeation prevention layer is in contact with or furthercomprises an adhesive composition or adhesive layer.

5. The construction of paragraph 4 wherein said adhesive compositionprovides an adhesion level to a substrate sufficient to permit thecombination of said construction and said substrate to suitablyfunction.

6. The construction of paragraph 5 wherein said functional adhesion isobtained as a consequence of vulcanization of the adhesive composition.

7. The construction of paragraph 4 or 5 wherein said adhesivecomposition comprises epoxidized styrene-butadiene-styrene blockcopolymer.

8. The construction of any of paragraphs 1 to 7 wherein saidthermoplastic layer comprises a polymer selected from the groupconsisting of homopolymers and copolymers of polyolefins, styrenics,vinyls, acrylics, fluorocarbons, diene polymers and mixtures thereof.

9. The construction of any of paragraphs 1 to 8 wherein said at leastone filler is selected from the group consisting of carbon black, clay,exfoliating clay, calcium carbonate, mica, silica, silicates, talc,titanium dioxide, wood flour and mixtures thereof.

10. The construction of paragraph 9 wherein said at least one filler isselected from the group consisting of carbon black, exfoliating clay andmixtures thereof.

11. The construction of any of paragraphs 1 to 10 wherein said at leastone cure system comprises at least one curing agent and at least oneaccelerator.

12. The construction of any of paragraphs 1 to 11 wherein said fluidpermeation prevention layer further comprises an additive selected fromthe group consisting of pigments, plasticizers, reactive softeners,antioxidants, antiozonants, processing aids, tackifiers, and mixturesthereof,

13. The construction of any of paragraphs 1 to 12 suitable for use in atire wherein said layer comprising at least one engineering resin is aninnerliner layer and said layer comprising said high diene rubber is acarcass layer or sidewall layer or both.

14. The construction of any of paragraphs 1 to 13 wherein thethermoplastic resin component is selected from the group consisting ofpolyamide resins, polyester resins, polynitrile resins, polymethacrylateresins, polyvinyl resins, cellulose resins, fluororesins, imide resinsand mixtures thereof.

15. The construction of paragraph 1 to 13 wherein the thermoplasticresin component is an engineering resin selected from the groupconsisting of nylon 6, nylon 66, nylon 46, nylon 11, nylon 12, nylon610, nylon 612, nylon 6/66 copolymer, nylon 6/66/610 copolymer, nylonMXD6, nylon 6T, nylon 6/6T copolymer, nylon 66/PP copolymer, nylon66/PPS copolymer, polybutylene terephthalate, polyethyleneterephthalate, polyethylene isophthalate, polyethyleneterephthalate/polyethylene isophthalate copolymer, polyacrylate,polybutylene naphthalate, liquid crystal polyester, polyoxyalkylenediimidate/polybutyrate terephthalate copolymer, polyacrylonitrile,polymethacrylonitrile, acrylonitrile/styrene copolymer,methacrylonitrile/styrene copolymer, methacrylonitrile/styrene/butadienecopolymer, polymethyl methacrylate, polyethyl methacrylate, ethylenevinyl acetate, polyvinyl alcohol, vinyl alcohol/ethylene copolymer,polyvinylidene chloride, polyvinyl chloride, vinyl chloride/vinylidenechloride copolymer, vinylidene chloride/methylacrylate copolymer,cellulose acetate, cellulose acetate butyrate, polyvinylidene fluoride,polyvinyl fluoride, polychlorofluoroethylene,tetrafluoroethylene/ethylene copolymer, aromatic polyimides, andmixtures thereof.

16. The construction of any of paragraphs 1 to 15 wherein said at leastone elastomer component B is selected from the group consisting ofnatural rubber, synthetic polyisoprene rubber, epoxylated naturalrubber, styrene-butadiene rubber (SBR), polybutadiene rubber (BR),nitrile-butadiene rubber (NBR), hydrogenated NBR, hydrogenated SBR;ethylene propylene diene monomer rubber (EPDM), ethylene propylenerubber (EPM), maleic acid-modified ethylene propylene rubber (M-EPM),butyl rubber (IIR), isobutylene-aromatic vinyl or diene monomercopolymers, brominated-IIR, chlorinated-IIR, brominated isobutylenep-methylstyrene copolymer, chloroprene rubber, epichlorohydrinhomopolymers rubber, epichlorohydrin-ethylene oxide or allyl glycidylether copolymer rubbers, epichlorohydrin-ethylene oxide-allyl glycidylether terpolymer rubbers, chlorosulfonated polyethylene, chlorinatedpolyethylene, maleic acid-modified chlorinated polyethylene, methylvinylsilicone rubber, dimethyl silicone rubber, methylphenylvinyl siliconerubber, polysulfide rubber, vinylidene fluoride rubbers,tetrafluoroethylene-propylene rubbers, fluorinated silicone rubbers,fluorinated phosphagen rubbers, styrene elastomers, thermoplastic olefinelastomers, polyester elastomers, urethane elastomers, and polyamideelastomers.

17. The construction of any of paragraphs 1 to 16 wherein said at leastone elastomer component B is selected from the group consisting of ahalide of a C₄ to C₇ isomonoolefin and p-alkylstyrene copolymer,brominated isobutylene p-methylstyrene copolymer, hydrogenatednitrile-butadiene rubber, acrylonitrile butadiene rubber,chlorosulfonated polyethylene, chlorinated polyethylene, epichlorohydrinrubber, chlorinated butyl rubber, and brominated butyl rubber.

18. The construction of any of paragraphs 1 to 17 wherein said elastomercomponent of said fluid permeation prevention layer is substantiallyfully vulcanized.

19. The construction of paragraph 8 wherein said thermoplastic isselected from the group consisting of ethylene homopolymers, ethylenecopolymers, low density polyethylene, linear low density polyethylene,high density polyethylene, ethylene-styrene copolymer,ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexenecopolymer, ethylene-octene copolymer and mixtures thereof.

20. The construction of any of paragraphs 2 to 19 wherein saidthermoplastic polymer exhibits a glass transition temperature, Tg, ofless than about −20° C.

21. The construction of any of paragraphs 1 to 20 further comprising anadhesive layer or adhesive composition between said thermoplastic layerand said fluid permeation prevention layer.

22. An article comprising:

-   -   (A) a first layer comprising an elastomer;    -   (B) a second layer comprising a dynamically vulcanized alloy of        an engineering resin and a copolymer of an isoolefin and a        para-alkylstyrene, said second layer having fluid permeation        prevention properties; and    -   (C) a substantially hydrophobic thermoplastic layer having an        upper and a lower surface and comprising a film-forming,        semi-crystalline, substantially hydrophobic carbon chain polymer        having a glass transition temperature, Tg, of less than about        −20° C.;        wherein said upper or said lower surface of said second layer is        adjacent said first layer, and the other of said upper or said        lower surface of said thermoplastic layer is adjacent a fluid.

23. The article of paragraph 22 wherein said engineering resin isselected from the group consisting of polyamide resins, polyesterresins, polynitrile resins, poly(meth)acrylate resins, polyvinyl resins,cellulose resins, fluorine resins, imide resins and mixtures thereof.

24. The article of paragraph 22 or 23 wherein said first layer elastomeris selected from the group consisting of at least one halogenatedelastomer and at least one high diene rubber.

25. The article of paragraph 24 wherein said first layer elastomer isselected from the group consisting of a halogen-containing randomcopolymer of a C₄ to C₇ isomonoolefin and a para-alkylstyrene, saidpara-alkylstyrene comprising about 0.5 weight percent to about 20 weightpercent of said copolymer, a halogen-containing random copolymer of a C₄to C₁₂ isomonoolefin and a C₄ to C₁₄ multiolefin, said halogen selectedfrom the group consisting of chlorine, bromine and mixtures thereof; anatural or synthetic rubber comprising at least 50 mole % of dienemonomer and selected from the group consisting of polyisoprene,polybutadiene, poly(styrene-co-butadiene),poly(styrene-butadiene-styrene) block copolymer, natural rubber; andmixtures thereof.

26. The article of paragraph 23 wherein said engineering resin isselected from the group consisting of nylon 6, nylon 66, nylon 46, nylon11, nylon 12, nylon 610, nylon 612, nylon 6/66 copolymer, nylon 6/66/610copolymer, nylon MXD6, nylon 6T, nylon 6/6T copolymer, nylon 66/PPcopolymer, nylon 66/PPS copolymer, polybutylene terephthalate,polyethylene terephthalate, polyethylene isophthalate, polyethyleneterephthalate/polyethylene isophthalate copolymer, polyacrylate,polybutylene naphthalate, liquid crystal polyester, polyoxyalkylenediimide diacid/polybutyrate terephthalate copolymer, polyacrylonitrile,polymethacrylonitrile, acrylonitrile/styrene copolymer,methacrylonitrile/styrene copolymer, methacrylonitrile/styrene/butadienecopolymer, polymethyl methacrylate, polyethyl methacrylate, ethylenevinyl acetate, polyvinyl alcohol, vinyl alcohol/ethylene copolymer,polyvinylidene chloride, polyvinyl chloride, polyvinyl/polyvinylidenecopolymer, vinylidene chloride/methylacrylate copolymer, celluloseacetate, cellulose acetate butyrate, polyvinylidene fluoride, polyvinylfluoride, polychlorofluoroethylene, tetrafluoroethylene/ethylenecopolymer, aromatic polyimides, and mixtures thereof.

27. The article of any of paragraphs 22 to 26 wherein said thermoplasticpolymer has an equilibrium water content at 100% relative humidity ofless than about 0.1 g per 100 g polymer or a molar water content perpolymer structural unit of less than about 0.1.

28. The article of any of paragraphs 22 to 27 wherein said thermoplasticlayer comprises a polymer selected from the group consisting ofhomopolymers and copolymers of polyolefins, ethylene homopolymers,ethylene copolymers, styrenics, vinyls, acrylics, fluorocarbons, dienepolymers and mixtures thereof.

29. The article of paragraph 28 wherein said thermoplastic layercomprises low density polyethylene.

30. The article of any of paragraphs 22 to 29 further comprising anadhesive composition or adhesive layer situated between saidsubstantially hydrophobic thermoplastic layer and said fluid permeationprevention layer.

31. The article of paragraph 30 wherein said adhesive composition oradhesive layer comprises at least one polymer or copolymer selected fromthe group consisting of maleated ethylene copolymers, epoxidizedethylene copolymers, ethylene ionomers, ethylene acrylate copolymers,ethylene vinyl acetate copolymers and mixtures thereof.

32. The article of paragraph 30 wherein said adhesive layer or adhesivecomposition is about 1 micron to about 15 microns thick.

33. The article of any of paragraphs 22 to 32 further comprising asecond substantially hydrophobic thermoplastic layer between said fluidpermeation prevention layer and said first elastomer containing layer.

34. The article of paragraph 33 further comprising an adhesivecomposition or adhesive layer situated between said substantiallyhydrophobic thermoplastic layer and said first elastomer containinglayer.

35. The article of any of paragraphs 22 to 34 substantially in the formof a hose.

36. A pneumatic tire comprising an inner air chamber and an outer treadand sidewall portion, an inner carcass portion having a top surfaceadhered or bonded to said tread and sidewall portion and a bottomsurface, a laminated innerliner layer having a top surface and a bottomsurface, wherein the top surface of said innerliner layer is adhered orbonded to the bottom surface of said carcass layer and the bottomsurface of said innerliner layer being the innermost surface in contactwith the air present in said air chamber, said innerliner layercomprising an engineering resin and at least one thermoplastic layer inlaminate relation with at least said bottom innerliner surface, saidthermoplastic layer comprising a film-forming, semi-crystalline,substantially hydrophobic carbon chain polymer having a glass transitiontemperature, Tg, of less than about −20° C.

37. The pneumatic tire of paragraph 36 wherein said innerliner layercomprises a dynamically vulcanized alloy of an engineering resin and ahalogen-containing random elastomeric copolymer of a C₄ to C₇isomonoolefin and a para-alkylstyrene, said para-alkylstyrene comprisingabout 0.5 to about 20 weight percent of said copolymer, wherein saidelastomeric copolymer is dispersed in a vulcanized state, as adiscontinuous phase, in a matrix of said engineering resin.

38. The pneumatic tire of paragraph 36 wherein said innerliner layercomprises a dynamically vulcanized alloy of an engineering resin and ahalogen-containing random elastomeric copolymer of a C₄ to C₁₂isomonoolefin and a C₄ to C₁₄ multiolefin, wherein said elastomericcopolymer is dispersed in a vulcanized state, as a discontinuous phase,in a matrix of said engineering resin.

39. The pneumatic tire of paragraph 37 wherein said tire is vulcanized.

40. A method for fabricating a pneumatic tire comprising a carcasselement containing a high diene rubber and an innerliner layer as theinnermost layer of said tire, comprising the steps of:

-   -   (A) providing an innerliner layer comprising a substantially        vulcanized halogenated isomonoolefin-containing elastomer        dispersed in particulate form in an engineering resin, said        innerliner layer having an upper and a lower surface;    -   (B) providing a first thermoplastic layer in laminate relation        with at least said lower surface of said innerliner layer, said        thermoplastic layer comprising a film-forming, semi-crystalline,        substantially hydrophobic carbon chain polymer having a glass        transition temperature, Tg, of less than about −20° C.;    -   (C) contacting the upper surface of said innerliner layer with        said carcass element to form a further laminated structure; and    -   (D) heating and forming said laminated structure under pressure        to the desired shape of a tire at a temperature of from about        100° C. to about 250° C. for a period of time sufficient to        substantially vulcanize said structure.

41. The method of paragraph 40 further comprising a second thermoplasticlayer in laminate relation with said upper surface of said innerlinerlayer, said second thermoplastic layer comprising a film-forming,semi-crystalline, substantially hydrophobic carbon chain polymer havinga glass transition temperature, Tg, of less than about −20° C.; whereinsaid first thermoplastic layer, said second thermoplastic layer or bothare in contact with an adhesive composition or adhesive layer betweensaid thermoplastic layer and said fluid permeation prevention layer,between said thermoplastic layer and said carcass or both.

42. The method of paragraph 41 wherein said adhesive layer comprisesepoxidized styrenic block copolymer.

43. The tire of paragraph 36 selected from the group consisting of tiressuitable for use on automobiles, trucks, construction vehicles,recreational vehicles and farm vehicles.

44. A pneumatic tire comprising an outer tread layer, intermediatesidewall and carcass layers and an innermost air permeation preventionlayer:

(i) said air permeation prevention layer having an upper and a lowersurface, said layer comprising a polymer composition having an airpermeation coefficient of about 25×10⁻¹² cc cm/cm² sec cmHg (at 30° C.)or less and a Young's modulus of about 1 MPa to about 500 MPa, saidpolymer composition comprising:

-   -   (A) at least 10% by weight, based on the total weight of the        polymer composition, of at least one thermoplastic resin        component having an air permeation coefficient of about 25×10⁻¹²        cc cm/cm² sec cmHg (at 30° C.) or less and a Young's modulus of        more than 500 MPa, which resin component is selected from the        group consisting of polyamide resins, polyester resins,        polynitrile resins, polymethacrylate resins, polyvinyl resins,        cellulose resins, fluororesins, and imide resins, and    -   (B) at least 10% by weight, based on the total weight of said        polymer composition, of at least one elastomer component having        an air permeation coefficient of more than about 25×10⁻¹² cc        cm/cm² sec cmHg (at 30° C.) and a Young's modulus of not more        than 500 MPa, which elastomer component is selected from the        group consisting of diene rubbers and the hydrogenates thereof,        halogen-containing rubbers, silicone rubbers, sulfur-containing        rubbers, fluoro-rubbers, hydrin rubbers, acryl rubbers, ionomers        and thermoplastic elastomers, the total amount (A)+(B) of the        component (A) and the component (B) being not less than about        30% by weight based on the total weight of said polymer        composition, wherein the elastomer component (B) is dispersed in        a vulcanized state, as a discontinuous phase, in a matrix of the        thermoplastic resin component (A) in said polymer composition;        and

(ii) at least one thermoplastic layer in laminate relation with at leastsaid lower surface of said air permeation prevention layer, saidthermoplastic layer comprising a film-forming, semi-crystalline,substantially hydrophobic carbon chain polymer having a glass transitiontemperature, Tg, of less than about −20° C.

45. A pneumatic tire as claimed in paragraph 44, further comprising anadhesive composition or adhesive layer between said thermoplastic layerand said fluid permeation prevention layer.

46. A pneumatic tire as claimed in paragraph 44 or 45, furthercomprising a thermoplastic layer in laminate relation with at said uppersurface of said innerliner layer, said thermoplastic layer comprising afilm-forming, semi-crystalline, substantially hydrophobic carbon chainpolymer having a glass transition temperature, Tg, of less than about−20° C. and further comprising an adhesive layer between thethermoplastic layer laminated to the upper surface of said innerlinerlayer and said carcass layer.

47. The pneumatic tire of paragraph 46 wherein said adhesive layercomprises epoxidized styrenic block copolymer.

48. A pneumatic tire as described in paragraph 44 wherein said component(i) (A) is at least one polyamide resin, and said component (i) (B) isat least one bromine-containing random elastomeric copolymer of a C₄ toC₇ isomonoolefin and a para-alkylstyrene.

49. A pneumatic tire as described in paragraph 45, wherein said adhesivelayer comprises at least one polymer selected from the group consistingof ethylene acrylic ester terpolymers comprising at least one ofmethyl-acrylate, ethyl-acrylate or butyl-acrylate; and at least one ofmaleic anhydride or glycidyl methacrylate.

50. A vulcanizable layered construction comprising at least twoelastomer-containing layers and at least one thermoplastic film layer,the first of said two elastomer-containing layers characterized as afluid permeation prevention layer, the second of said at least twoelastomer-containing layers comprising at least one high diene rubber;said thermoplastic film layer comprising at least one thermoplastic,film-forming, semi-crystalline, substantially hydrophobic carbon chainpolymer having a glass transition temperature, Tg, of less than about−20° C.;

wherein said layers are arranged in an order selected from thefollowing: (1) said at least one thermoplastic film layer, said fluidpermeation prevention layer and said high diene rubber containing layer;or (2) said fluid permeation prevention layer, said high diene rubbercontaining layer, and said at least one thermoplastic film layer, andsaid fluid permeation prevention layer comprises a composition having aYoung's modulus of about 1 MPa to about 500 MPa said compositioncomprising:

-   -   (A) at least 10% by weight, based on the total weight of the        polymer composition, of at least one thermoplastic resin        component having a Young's modulus of more than 500 MPa, which        resin component is selected from the group consisting of        polyamide resins, polyester resins, polynitrile resins,        polymethacrylate resins, polyvinyl resins, cellulose resins,        fluororesins, and imide resins, and    -   (B) at least 10% by weight, based on the total weight of the        polymer composition, of at least one elastomer component having        a Young's modulus of not more than 500 MPa, which elastomer        component is selected from the group consisting of diene rubbers        and the hydrogenates thereof, halogen-containing rubbers,        silicone rubbers, sulfur-containing rubbers, fluoro-rubbers,        hydrin rubbers, acryl rubbers, ionomers and thermoplastic        elastomers, the total amount (A)+(B) of the component (A) and        the component (B) being not less than 30% by weight based on the        total weight of the polymer composition, wherein said elastomer        component (B) is dispersed in a substantially vulcanized state,        as a discontinuous phase, in a matrix of the thermoplastic resin        component (A) in the polymer composition.

51. The construction of paragraph 50, said layers arranged in the order(1) and further comprising a second thermoplastic film layer, saidsecond thermoplastic film layer between said fluid permeation preventionlayer and said high diene rubber-containing layer, said secondthermoplastic film layer comprising a film-forming, semi-crystalline,substantially hydrophobic carbon chain polymer having a glass transitiontemperature, Tg, of less than about −20° C.

52. The construction of paragraph 51 further comprising at least oneadhesive layer between (1) said thermoplastic film layer and said fluidpermeation prevention layer, (2) between said second thermoplastic filmlayer and said high diene rubber-containing layer or between both (1)and (2).

53. The construction of paragraph 50, 51, or 52 further comprising anadditive selected from the group consisting of pigments, antioxidants,antiozonants, processing aids, tackifiers, and mixtures thereof.

54. The construction of any of paragraphs 50 to 53 suitable for use in atire wherein said layer comprising at least one engineering resin is atire innerliner layer and said layer comprising said high diene rubberis a tire carcass layer or tire sidewall layer or both.

55. The construction of any of paragraphs 50 to 54 wherein saidengineering resin is selected from the group consisting of polyamideresins, polyester resins, polynitrile resins, polymethacrylate resins,polyvinyl resins, cellulose resins, fluororesins, imide resins andmixtures thereof.

56. The construction of any of paragraphs 50 to 54 wherein saidengineering resin is selected from the group consisting of nylon 6,nylon 66, nylon 46, nylon 11, nylon 12, nylon 610, nylon 612, nylon 6/66copolymer, nylon 6/66/610 copolymer, nylon MXD6, nylon 6T, nylon 6/6Tcopolymer, nylon 66/PP copolymer, nylon 66/PPS copolymer, polybutyleneterephthalate, polyethylene terephthalate, polyethylene isophthalate,polyethylene terephthalate/polyethylene isophthalate copolymer,polyacrylate, polybutylene naphthalate, liquid crystal polyester,polyoxyalkylene diimidate/polybutyrate terephthalate copolymer,polyacrylonitrile, polymethacrylonitrile, acrylonitrile/styrenecopolymer, methacrylonitrile/styrene copolymer,methacrylonitrile/styrene/butadiene copolymer, polymethyl methacrylate,polyethyl methacrylate, ethylene vinyl acetate, polyvinyl alcohol, vinylalcohol/ethylene copolymer, polyvinylidene chloride, polyvinyl chloride,vinyl chloride/vinylidene chloride copolymer, vinylidenechloride/methylacrylate copolymer, cellulose acetate, cellulose acetatebutyrate, polyvinylidene fluoride, polyvinyl fluoride,polychlorofluoroethylene, tetrafluoroethylene/ethylene copolymer,aromatic polyimides, and mixtures thereof.

57. The construction of any of paragraphs 50 to 56 wherein said at leastone elastomer component B is selected from the group consisting ofnatural rubber, synthetic polyisoprene rubber, epoxylated naturalrubber, styrene-butadiene rubber (SBR), polybutadiene rubber (BR),nitrile-butadiene rubber (NBR), hydrogenated NBR, hydrogenated SBR;ethylene propylene diene monomer rubber (EPDM), ethylene propylenerubber (EPM), maleic acid-modified ethylene propylene rubber (M-EPM),butyl rubber (HR), isobutylene-aromatic vinyl or diene monomercopolymers, brominated-IIR, chlorinated-IIR, brominated isobutylenep-methylstyrene copolymer, chloroprene rubber, epichlorohydrinhomopolymers rubber, epichlorohydrin-ethylene oxide or allyl glycidylether copolymer rubbers, epichlorohydrin-ethylene oxide-allyl glycidylether terpolymer rubbers, chlorosulfonated polyethylene, chlorinatedpolyethylene, maleic acid-modified chlorinated polyethylene, methylvinylsilicone rubber, dimethyl silicone rubber, methylphenylvinyl siliconerubber, polysulfide rubber, vinylidene fluoride rubbers,tetrafluoroethylene-propylene rubbers, fluorinated silicone rubbers,fluorinated phosphagen rubbers, styrene elastomers, thermoplastic olefinelastomers, polyester elastomers, urethane elastomers, and polyamideelastomers.

58. The construction of any of paragraphs 50 to 57 wherein said at leastone elastomer component B is selected from the group consisting of ahalide of a C₄ to C₇ isomonoolefin and p-alkylstyrene copolymer,brominated isobutylene p-methylstyrene copolymer, hydrogenatednitrile-butadiene rubber, acrylonitrile butadiene rubber,chlorosulfonated polyethylene, chlorinated polyethylene, epichlorohydrinrubber, chlorinated butyl rubber, and brominated butyl rubber.

59. The construction of any of paragraphs 50 to 58 wherein saidelastomer component of said fluid permeation prevention layer issubstantially fully vulcanized.

60. The vulcanized construction of any of paragraphs 50 to 59.

61. An article comprising the vulcanizable construction of any ofparagraphs 50 to 60.

62. The article of paragraph 61 selected from the group consisting ofhoses and pneumatic tire components.

63. A pneumatic tire comprising an outer tread layer, intermediatesidewall and carcass layers and an innermost air permeation preventionlayer:

(i) said air permeation prevention layer having an upper and a lowersurface, said layer

comprising a polymer composition having an air permeation coefficient ofabout 25×10⁻¹² cc cm/cm² sec cmHg (at 30° C.) or less and a Young'smodulus of about 1 MPa to about 500 MPa, said polymer compositioncomprising:

-   -   (A) at least 10% by weight, based on the total weight of the        polymer composition, of at least one thermoplastic resin        component having an air permeation coefficient of about 25×10⁻¹²        cc cm/cm² sec cmHg (at 30° C.) or less and a Young's modulus of        more than 500 MPa, which resin component is selected from the        group consisting of polyamide resins, polyester resins,        polynitrile resins, polymethacrylate resins, polyvinyl resins,        cellulose resins, fluororesins, and imide resins, and    -   (B) at least 10% by weight, based on the total weight of said        polymer composition, of at least one elastomer component having        an air permeation coefficient of more than about 25×10⁻¹² cc        cm/cm² sec cmHg (at 30° C.) and a Young's modulus of not more        than 500 MPa, which elastomer component is selected from the        group consisting of diene rubbers and the hydrogenates thereof,        halogen-containing rubbers, silicone rubbers, sulfur-containing        rubbers, fluoro-rubbers, hydrin rubbers, acryl rubbers, ionomers        and thermoplastic elastomers, the total amount (A)+(B) of the        component (A) and the component (B) being not less than about        30% by weight based on the total weight of said polymer        composition, wherein the elastomer component (B) is dispersed in        a vulcanized state, as a discontinuous phase, in a matrix of the        thermoplastic resin component (A) in said polymer composition;        and

(ii) at least one thermoplastic layer in laminate relation with at leastsaid lower surface of said air permeation prevention layer, saidthermoplastic layer comprising a film-forming, semi-crystalline,substantially hydrophobic carbon chain polymer having a glass transitiontemperature, Tg, of less than about −20° C.

EXAMPLES

Compositions were prepared according to the following examples. Theamount of each component used is based on parts per hundred rubber (phr)present in the composition. The following commercially availableproducts were used for the components employed in the compositions ofthe examples:

Fluid Permeation Prevention Resin Components Description N11 (Nylon 11)Rilsan BMN O (Atochem) N6/66 (Nylon 6/66 copolymer) Ube 5033B (Ube) P1Plasticizer, BM4, N-butylsulfonamide (Daihachi Chemical Ind.) R1Reactive softener, AR201, maleated ethylene ethyl acrylate (EEA)copolymer (Mitsui-Dupont) Tg = −35° C. S1 Stabilizer package includesIrganox, Tinuvin, Copper Iodide (CuI) Rubber Component Description BIMSBrominated isobutylene p-methyl styrene copolymer, 0.75% Br, 5% PMS,ExxonMobil Chemical) Cure System Components Description-Function ZnOZinc oxide - cure system component St-acid Stearic acid - cure systemcomponent ZnSt Zinc sterate - cure system component HydrophobicThermoplastic Components Description-Function PE-1 Low densitypolyethylene (LDPE), LD-150BW (0.75 MI, 0.923 density, 240 MPa modulus,ExxonMobil Chemical) PE-2 Low density polyethylene (LDPE), Novatec LDLJ603 (7 MFR, 0.917 density, Japan Polyethylene Corp.)

In accordance with the compositions or formulations listed in Table 1,examples 1 and 2 were prepared using a dynamic vulcanization twin-screwextruder at 220° C. The elastomer component and vulcanization systemwere charged into a kneader, mixed for about 3.5 minutes and dumped outat a temperature of about 90° C. The mixture was then pelletized using arubber pelletizer. Premixing of the nylon components with plasticizerand stabilizers was performed using a Japan Steel Works, Ltd. Model 44(JSW-44) twin screw extruder at 210° C. All of the pre-blended nyloncomponents, including plasticizer and stabilizer, pre-compounded rubberpellets, and reactive softener were then metered into a JSW-44 twinscrew extruder at 220° C. for extrusion mixing and dynamicvulcanization. Extrudates were cooled in a water bath, pelletized anddried.

TABLE 1 Example (phr) 1 2 BIMS 100 100 ZnO 0.15 0.15 St-acid 0.60 0.60ZnSt 0.30 0.30 N11 40.4 0 N6/66 27.8 66.5 P1 11.0 23.4 R1 10.1 10.0 S10.51 0.50 Permeability* 20 21 M50, RT** 4.1 6.0 EB (%), RT** 380 400*Permeability test: oxygen permeability at 30° C. measured according toJIS K7126 test standard in units of 10⁻¹² cm³-cm/cm²-sec-cmHg **M50 =50% modulus in units of MPa, measured at room temperature (RT)(according to ASTM D412-92); EB = elongation at break measured at roomtemperature (according to ASTM D412-92).

An A/B/A laminate was prepared where layer A is PE1 and layer B is thecomposition of Example 1. The laminate was formed using a W&H(Windmoeller & Hoelscher Corp., Lincoln, R.I., USA) co-extrusion blownfilm line with 250 mm die and three 60/90/60 mm extruders. The linespeeds were about 65 kg/h for PE1 and about 70 kg/h for the compositionof Example 1 with a blow-up ratio of 2. An A/B laminate was preparedusing a Brampton (Brampton Engineering, Brampton, Ontario, CA)co-extrusion blown film line with 100 mm die and two 50/75 mm extruderswhere A is PE2 and B is the composition of Example 2. The line speed wasabout 0.5 kg/h for PE2 and 1 kg/h for the composition of Example 2 witha blow-up ratio of 4. The moisture permeability comparison between thecomposition of Example 1 and PE1/Example 1/PE1 laminate is shown inTable 2 and the comparison between the composition of Example 2 andPE2/Example 2 laminate is shown in Table 3.

TABLE 2 Example 1 3 Material or Laminate Example 1 PE1/Example 1/PE1Thickness (microns) 100 52/106/52 MVTR* 8 2.5 MVTR = moisture vaportransmission rate in units of g/m²-day measured at 38° C. using aPermatran-W Model 3/61 tester (Mocon, Inc., Minneapolis, MN)

TABLE 3 Example 2 4 Material or Laminate Example 2 PE2/Example 2Thickness (microns) 170 70/171 MVTR 16 8 E′ (−40° C.) 370 280 E′ (−20°C.) 294 225 E′ (20° C.) 140 192 MVTR = moisture vapor transmission ratein g/m²-day measured at 38° C. using a Permatran-W Model 3/61 tester(Mocon, Inc., Minneapolis, MN) E′ = dynamic storage modulus in MPameasured using a Rheometric DMTA, dynamic mechanical thermal analysis,temperature scan at 1 Hz (TA Instruments, Inc., New Castle, DE; formerlyRheometric Scientific).

-   -   As shown in Tables 2 and 3, lamination of a polyethylene film,        in this examples, LDPE, onto the thermoplastic elastomer        composition greatly lowers the moisture transmission rate of the        resulting laminate. In addition, using the soft or flexible LDPE        layer did not adversely affect the room temperature and low        temperature moduli of the thermoplastic elastomer.

All documents described herein are incorporated by reference herein,including any priority documents and/or testing procedures, to theextent they are not inconsistent with this disclosure. The principles,preferred embodiments, and modes of operation of the present inventionhave been described in the foregoing specification. Although theinvention herein has been described with reference to particularembodiments, it is to be understood that these embodiments are merelyillustrative of the principles and applications of the presentinvention. It is therefore to be understood that numerous modificationsmay be made to the illustrative embodiments and that other arrangementsmay be devised without departing from the spirit and scope of thepresent invention as defined by the appended claims.

1. A layered construction comprising at least three layers, one of whichlayers comprising a fluid permeation prevention layer having an upperand a lower surface; at least one thermoplastic layer in laminaterelation with at least said fluid permeation prevention layer lowersurface, said thermoplastic layer comprising a film-formingsemi-crystalline carbon chain polymer having a glass transitiontemperature, Tg, of less than about −20° C.; and a layer comprising atleast one high diene rubber; wherein said fluid permeation preventionlayer comprises a polymer composition having an air permeationcoefficient of 25×10⁻¹² cc·cm/cm² sec cmHg (at 30° C.) or less and aYoung's modulus of 1 to 500 MPa, said layer of said polymer compositioncomprising: (A) at least 10% by weight, based on the total weight of thepolymer composition, of at least one thermoplastic resin componenthaving an air permeation coefficient of 25×10⁻¹² cc·cm/cm² sec cmHg (at30° C.) or less and a Young's modulus of more than 500 MPa, which resincomponent is selected from the group consisting of polyamide resins,polyester resins, polynitrile resins, polymethacrylate resins, polyvinylresins, cellulose resins, fluororesins, and imide resins, and (B) atleast 10% by weight, based on the total weight of the polymercomposition, of at least one elastomer component having an airpermeation coefficient of more than 25×10⁻¹² cc·cm/cm² sec cmHg (at 30°C.) and a Young's modulus of not more than 500 MPa, which elastomercomponent is selected from the group consisting of diene rubbers and thehydrogenates thereof, halogen-containing rubbers, silicone rubbers,sulfur-containing rubbers, fluoro-rubbers, hydrin rubbers, acrylrubbers, ionomers and thermoplastic elastomers, the total amount (A)+(B)of the component (A) and the component (B) being not less than 30% byweight based on the total weight of the polymer composition, wherein theelastomer component (B) is dispersed in a vulcanized state, as adiscontinuous phase, in a matrix of the thermoplastic resin component(A) in the polymer composition.
 2. The construction of claim 1 whereinsaid thermoplastic polymer has an equilibrium water content at 100%relative humidity of less than about 0.1 g per 100 g polymer or a molarwater content per polymer structural unit of less than about 0.1.
 3. Theconstruction of claim 1 further comprising a second thermoplastic layer,the thermoplastic of said second thermoplastic layer being the same ordifferent from said first thermoplastic layer and wherein said secondthermoplastic layer is in laminate relation with the other of said upperand lower surfaces of said fluid permeation prevention layer.
 4. Theconstruction of claim 1 wherein: (1) when said construction comprisesone thermoplastic layer, said surface of said fluid permeationprevention layer not in contact with said thermoplastic layer furthercomprises an adhesive composition; and (2) when said constructioncomprises two thermoplastic layers each having surfaces, a surface ofone of said thermoplastic layers not in contact with said fluidpermeation prevention layer is in contact with or further comprises anadhesive composition or adhesive layer.
 5. (canceled)
 6. (canceled) 7.(canceled)
 8. The construction of claim 1 wherein said thermoplasticlayer comprises a polymer selected from the group consisting ofhomopolymers and copolymers of polyolefins, styrenics, vinyls, acrylics,fluorocarbons, diene polymers and mixtures thereof.
 9. (canceled) 10.(canceled)
 11. (canceled)
 12. (canceled)
 13. The construction of claim 1suitable for use in a tire wherein said layer comprising at least onefluid permeation prevention layer is an innerliner layer and said layercomprising said high diene rubber is a carcass layer or sidewall layeror both.
 14. The construction of claim 1 wherein said thermoplasticresin component is selected from the group consisting of polyamideresins, polyester resins, polynitrile resins, polymethacrylate resins,polyvinyl resins, cellulose resins, fluororesins, imide resins andmixtures thereof.
 15. (canceled)
 16. The construction of claim 1 whereinsaid at least one elastomer component B is selected from the groupconsisting of natural rubber, synthetic polyisoprene rubber, epoxylatednatural rubber, styrene-butadiene rubber (SBR), polybutadiene rubber(BR), nitrile-butadiene rubber (NBR), hydrogenated NBR, hydrogenatedSBR; ethylene propylene diene monomer rubber (EPDM), ethylene propylenerubber (EPM), maleic acid-modified ethylene propylene rubber (M-EPM),butyl rubber (IIR), isobutylene-aromatic vinyl or diene monomercopolymers, brominated-IIR, chlorinated-IIR, brominated isobutylenep-methylstyrene copolymer, chloroprene rubber, epichlorohydrinhomopolymers rubber, epichlorohydrin-ethylene oxide or allyl glycidylether copolymer rubbers, epichlorohydrin-ethylene oxide-allyl glycidylether terpolymer rubbers, chlorosulfonated polyethylene, chlorinatedpolyethylene, maleic acid-modified chlorinated polyethylene, methylvinylsilicone rubber, dimethyl silicone rubber, methylphenylvinyl siliconerubber, polysulfide rubber, vinylidene fluoride rubbers,tetrafluoroethylene-propylene rubbers, fluorinated silicone rubbers,fluorinated phosphagen rubbers, styrene elastomers, thermoplastic olefinelastomers, polyester elastomers, urethane elastomers, and polyamideelastomers.
 17. (canceled)
 18. (canceled)
 19. The construction of claim8 wherein said thermoplastic is selected from the group consisting ofethylene homopolymers, ethylene copolymers, low density polyethylene,linear low density polyethylene, high density polyethylene,ethylene-styrene copolymer, ethylene-propylene copolymer,ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octenecopolymer and mixtures thereof.
 20. (canceled)
 21. (canceled)
 22. Anarticle comprising: (A) a first layer comprising an elastomer; (B) asecond layer comprising a dynamically vulcanized alloy of an engineeringresin and a copolymer of an isoolefin and a para-alkylstyrene, saidsecond layer having fluid permeation prevention properties; and (C) asubstantially hydrophobic thermoplastic layer having an upper and alower surface and comprising a film-forming, semi-crystalline,substantially hydrophobic carbon chain polymer having a glass transitiontemperature, Tg, of less than about −20° C.; wherein said upper or saidlower surface of said second layer is adjacent said first layer, and theother of said upper or said lower surface of said thermoplastic layer isadjacent a fluid.
 23. (canceled)
 24. (canceled)
 25. (canceled) 26.(canceled)
 27. The article of claim 22 wherein said thermoplasticpolymer has an equilibrium water content at 100% relative humidity ofless than about 0.1 g per 100 g polymer or a molar water content perpolymer structural unit of less than about 0.1.
 28. The article of claim22 wherein said thermoplastic layer comprises a polymer selected fromthe group consisting of homopolymers and copolymers of polyolefins,ethylene homopolymers, ethylene copolymers, styrenics, vinyls, acrylics,fluorocarbons, diene polymers and mixtures thereof.
 29. (canceled) 30.The article of claim 22 further comprising an adhesive composition oradhesive layer situated between said substantially hydrophobicthermoplastic layer and said fluid permeation prevention layer.
 31. Thearticle of claim 30 wherein said adhesive composition or adhesive layercomprises at least one polymer or copolymer selected from the groupconsisting of maleated ethylene copolymers, epoxidized ethylenecopolymers, ethylene ionomers, ethylene acrylate copolymers, ethylenevinyl acetate copolymers and mixtures thereof.
 32. The article of claim30 wherein said adhesive layer or adhesive composition is about 1 micronto about 15 microns thick.
 33. (canceled)
 34. (canceled)
 35. The articleof claim 22 substantially in the form of a hose.
 36. (canceled) 37.(canceled)
 38. (canceled)
 39. (canceled)
 40. (canceled)
 41. (canceled)42. (canceled)
 43. (canceled)
 44. A pneumatic tire comprising an outertread layer, intermediate sidewall and carcass layers and an innermostair permeation prevention layer: (i) said air permeation preventionlayer having an upper and a lower surface, said layer comprising apolymer composition having an air permeation coefficient of about25×10⁻¹² cc cm/cm² sec cmHg (at 30° C.) or less and a Young's modulus ofabout 1 MPa to about 500 MPa, said polymer composition comprising: (A)at least 10% by weight, based on the total weight of the polymercomposition, of at least one thermoplastic resin component having an airpermeation coefficient of about 25×10⁻¹² cc cm/cm² sec cmHg (at 30° C.)or less and a Young's modulus of more than 500 MPa, which resincomponent is selected from the group consisting of polyamide resins,polyester resins, polynitrile resins, polymethacrylate resins, polyvinylresins, cellulose resins, fluororesins, and imide resins, and (B) atleast 10% by weight, based on the total weight of said polymercomposition, of at least one elastomer component having an airpermeation coefficient of more than about 25×10⁻¹² cc cm/cm² sec cmHg(at 30° C.) and a Young's modulus of not more than 500 MPa, whichelastomer component is selected from the group consisting of dienerubbers and the hydrogenates thereof, halogen-containing rubbers,silicone rubbers, sulfur-containing rubbers, fluoro-rubbers, hydrinrubbers, acryl rubbers, ionomers and thermoplastic elastomers, the totalamount (A)+(B) of the component (A) and the component (B) being not lessthan about 30% by weight based on the total weight of said polymercomposition, wherein the elastomer component (B) is dispersed in avulcanized state, as a discontinuous phase, in a matrix of thethermoplastic resin component (A) in said polymer composition; and (ii)at least one thermoplastic layer in laminate relation with at least saidlower surface of said air permeation prevention layer, saidthermoplastic layer comprising a film-forming, semi-crystalline,substantially hydrophobic carbon chain polymer having a glass transitiontemperature, Tg, of less than about −20° C.
 45. A pneumatic tire asclaimed in claim 44, further comprising an adhesive composition oradhesive layer between said thermoplastic layer and said fluidpermeation prevention layer.
 46. (canceled)
 47. (canceled) 48.(canceled)
 49. A pneumatic tire as claimed in claim 45, wherein saidadhesive layer comprises at least one polymer selected from the groupconsisting of ethylene acrylic ester terpolymers comprising at least oneof methyl-acrylate, ethyl-acrylate or butyl-acrylate; and at least oneof maleic anhydride or glycidyl methacrylate.
 50. (canceled) 51.(canceled)
 52. (canceled)
 53. (canceled)
 54. (canceled)
 55. (canceled)56. (canceled)
 57. (canceled)
 58. (canceled)
 59. (canceled) 60.(canceled)
 61. (canceled)
 62. (canceled)